Woolie_Wool's long post does an excellent job of showing that (at least in the West) people are much better off materially than they ever have been. Some people's lives will always suck, but now they are fewer, and their lives more tolerable.
If this reads like an incoherent stream of consciousness, I'm sorry.
The biggest drawback to modernity is the psychological toll it takes on a person. Our psyches evolved in environments exponentially different from our modern habitat, and because of humanity's unique capacity for cultural growth, our environment has changed at a pace our race has a very difficult time keeping up with. We have an instinctive desire to acquire knowledge. Despite all the [probably true] testimonies in this thread about people not caring about education, formal education does not have a monopoly on knowledge. We are just inquisitive beings. We have now reached a point where we have the technology to discover more about the universe than has ever been known. We also have centuries of discovery to look back upon. Humanity has accumulated a vast store of knowledge, and now we've reached a critical point. Our desire to learn about the world and to ascertain the truth is clashing with other psychological needs. The most obvious example of these "other needs" are the ones met by religion. As religious dogma crumbles from the scrutiny of rational and empirical investigation, faith too, crumbles. For some, this simply means living with a watered down version of their faith; for others, faith is abandoned all together. However, in a very small, very vocal minority, faith fights back. Fundamentalism rears its ugly head.
Once religion is gone, a void becomes present. I don't think it was until the existentialist movement of the 20th century that people began discussing this void freely. How many people are really satisfied with their lives? Who knows the anguish of the workman who whittles away his time in some trivial task, little more than a single bolt in a machine so large the whole cannot be seen from his perspective.
There is no "one size fits all" solution to the problems of modernity. Whether that is a bad thing is not for me to say. The responsibility lies with individuals to find meaning in their lives, and no one should allow anyone else to tell them what it is.
Well, culture is always a work in progress, and today's modernity is tomorrow's antiquity. The US is heading towards de-industrialization as the focus of our economy shifts to services, IT, etc. and business shifts and the Third World picks up the industrial slack, and that will invariably have profound effects on our society and lifestyles.
Of course, human beings are fundamentally the same creatures that lived tens of thousands of years ago in a much different world. The plague of obesity, for instance is partially caused by the human brain being wired for "feast or famine" diets--you either had a lot of food, for instance from a game kill or successful harvest, or little to none. In this case, the sensible option is to gorge yourself while you can get it, because it may be a while before you have significant access to food again. In modern society, a copious amount of food is always available, and this can cause the human eating drive to run completely amok.
Modern life and the anomie that comes with it is very problematic; it's possible to say this is weighed out by the luxuries we (well, some of us) have but that is a pretty superficial way of looking at it. A lot of it just sounds like "we may not be happy or have any meaning to our lives, but at least we have a bunch of shit and live for a long time."
The benefits of modern life are far from superficial. Imagine growing up in a pre-modern society. You will never have any hope of advancement in your life. You will do the job your father did and your father's father did, until you die (retirement? Forget it! If you can't work, you die!). You will work obscene hours (60 hour weeks were the norm in the early 20th century, I believe) in dangerous, back-breaking physical labor. You will likely never learn to read, or write, or understand much of the world around you.
From birth, you will be indoctrinated with religious lies with an intensity now only seen in the craziest backwoods redneck families. You will have Christianity and the threat of eternal damnation rammed down your throat. If you ever recant your faith, you will be tortured and executed in a macabre public spectacle. You will never be allowed to question the smallest detail of what you are taught.
The local constables or other keepers of the peace, through the authority of the king, will have total and unchecked power over your life (unless you lived in the United States during the 19th century, but the early US was not exactly the land of the free either, at least not on the local level). If you complain about your lot in life or complain about just about anything, you will be locked into a wooden board for hours while painfully bent over, strapped into a chair and subjected to a primitive form of waterboarding, or otherwise degraded. If you commit a more serious crime, you will be branded, flogged, or have a limb cut off (with a saw, none of this fancy surgery and anaesthesia bullshit), or a combination of those. In a relatively recent era, you will be locked in a cold and barren cell and subjected to starvation and unspeakable diseases from the awful condition of the food and water you do get.
In your childhood, you will be beaten and thrashed by your parents or your teachers, if you attend school, which you will likely not, for every possible lapse in behavior. You will get childhood diseases, many of which are now largely extinct, and there will be no medicine and no vaccinations to ease your suffering. From an early age you will be sent to the fields or factory, and will work as long and hard as the adults. At this point, there is a very good chance you will die before your eighteenth birthday.
Perhaps, on the cusp of adulthood, the military will snatch you up by force, and you will be thrown into brutal hand-to-hand or rank-firing combat, or aboard a rickety wooden ship, where you had a chance as good as one in three of dying right there. Should you miraculously survive being wounded, you will beg for sustenance or steal it for the remainder of your life. People will shoo you away and possibly kill you as you attempt to acquire food and clothing, and you will die, forgotten.
Should you survive youth, you will probably be married off to a woman, maybe a stranger. If you don't get along, tough shit--there is no such thing as divorce, and adultery ranges from a serious offense to punishable by death. If you are a homosexual, you will never reveal your sexual identity or indulge your feelings with another man on pain of brutal, violent, and very, very public death, as an example to other "sodomites". You will continue to work, scraping up barely enough money, food, or land (depending on the times and economy you live in) to survive. You will go hungry, you will work through pain and illness, you will pass on your ignorance and superstition to your numerous children. Some of them will die, and you will weep and mourn as you bury several of your own flesh and blood.
If you suffer from mental illness, perhaps they will just kill you, or lock you in an asylum not entirely dissimilar to one of the aforementioned prisons, except with doctors who may "experiment" with you. If you suffer from a bad injury, it will get infected, and you will die over several agonizing days or weeks.
After all this, you will still die young, with maybe forty years behind you. Maybe, if you were righteous enough, you believe that will go to heaven and be Jesus Christ's bitch for all eternity. If not, you will plunge into the lake of fire, where you will be burned, chewed up, violated, skewered, and subjected to tortures that the Spanish Inquisition would be proud of forever and ever and ever.
(Of coure, hell doesn't exist, but to a person living in the pre-modern world, it was as real as anything else.)
Is this the life you want?
The world can be a lonely, cruel place, but dismantling modern society is throwing the baby out with the bathwater and oversimplifying an extremely complex aspect of the human condition.