I am sure someone has asked this question before, but it is a reasonable question. Why has fantasy become increasingly popular over the last thirty years?
You can understand why science fiction was the rage during the fifties and sixties given the fact that we were all thinking that technology was going to save us. Not sure what it was going to save us from, but the adults weren't clear on that issue either except from the evil empires of the Soviet Union and Red China. But technology was definitely going to save us.
But why fantasy? I think it has something to do with yearnings. We yearn for some kind of life like you imagine being lived by these heroes and villains who never have to use the bathroom or make a living. Notice that Harry Potter doesn't have to worry about pocket change when in the Wizarding World, yet there are poor and wealthy there -- and exactly how do you earn a living in a land where you can conjure up just about anything you want anyway. And, by the way how did Harry's parents make that pile of galleons? Of course we do have the classic entrepeneurs Fred and George who make money selling mayhem -- is Rowling making fun of the business world there?
Seriously, I think that people from time to time kind of yearn for a medieval kind of life except with some of the luxuries of modern life like indoor plumbing, computers, and what not. But we are kind of caught up in it all. Not sure what the "in it all" means other than making a living so that you can afford to pay the doctor if you don't have insurance, pay to live where you live, put clothes on your back, etc. Perhaps medieval life is becoming more compelling given the fact that so many of us have discovered that guess what we can get caught up "in it all", but there just is no way we can pay for the "it all."
Maybe we do yearn for rulers who are either all good or all bad -- kind of an FDR vs. Hitler kind of world where we are clearly fighting on the side of the good guys. Perhaps the only way we can find such a world is in fantasy. For people who are really into fantasy, there is that small nagging hope somewhere back in your cortex or something that you really might meet an elf or a gnome -- and that would...would... would make you kind of special even if you couldn't pay the light bill.
That there really might be a little village somewhere on a humanscale like the hobbit village in The Lord of The Rings. You know that in medieval times those villages probably looked more like the muddy quagmires depicted in Braveheart as existing in Scotland in those times -- but maybe we have the know how now to actually make it happen.
Who wouldn't trade getting together with a bunch of friends and brewing up some ale, or putting out and harvesting a garden, and just enjoying each other and the long yarns you could spin.
Ahhhh... you can dream. Perhaps not, but then again.