WWW
Sad, but the way I think its headed
Interesting analysis, and I agree that this is a likely outcome. But it doesn't have to be.
What keeps the whole scene decrepit (and declining) is the small (and reducing) number of students, and the stone age attitudes of most flying school operators.
I fly a new-ish modern plane (not a Cessna or Piper) and most of my many non-aviation passengers have commented they really like flying like that, but they would never go anywhere near the old junk which sits around the airfield. It's pretty clear most "normal" people think along those lines, like it or not. Only a tiny percentage would turn up at a flying school to do a PPL. Many more people swallow their concerns for a single "trial lesson" for somebody's birthday, but that's no good for you.
BUT nobody stops somebody setting up a school with new modern planes. Contrary to what you say, there are plenty about. Look at the Diamond DA40 - sleek, efficient, and most importantly SEXY. Even a TB10 is vastly better than a PA28 into which everybody has to climb through the one door, crawling over the seats and wondering how they would get out if they really had to... A brand new C172 looks like something out of WW2 too. So why don't people do that? Lack of capital will be one reason given no doubt but where there is a business case, one can get money.
Perhaps the #1 reason is that most people IN this business reckon that spending 50hours in a C150 is the proper expression of manhood. These dinosaurs absolutely refuse to believe that somebody doesn't like these "wonderful old planes which are just perfect for training".
Next, you would have to advertise the fact that your planes are modern etc, and drive home to people that you don't fly the same old junk which they see everywhere. How many friends will that win you around your airfield? None (given the often vindictively political scene around airfields - itself the result of nobody making much money), so nobody will do it. I've known people set up with brand new planes but they refused to advertise the fact, for fear of making enemies (and they got no customers). But nothing stops you actually getting modern planes and promoting this huge marketing advantage in a way which any properly run business would.
The margin between direct operating costs of a plane (new one or old one) and what one can charge for a lesson, isn't big so the business case hinges severely on student numbers (aircraft utilisation). All the time these aren't there, one can argue about everything under the sun without getting anywhere. One can rant about taxes, licensing costs, landing fees, you name it. None of this makes any real difference when the "sales" aren't there.
Things could be done, but not without many/most of the dinosaurs disappearing first. This will take time, because many school operators are happy to work for next to nothing. It's a sort of a hobby, and all the time they make enough to pay their rent they will do the same old thing.
It needs a bold approach from an outsider, and it could be done only at certain locations. But I am quite sure that a properly run school, with a modern fleet, correct advertising, and proper facilities for post-PPL pilots, and a few other easy things, would succeed.