I never would have thought I'd reach a point in my life where I was arguing in defense of PE classes, although I basically reached that as soon as I wasn't in them anymore. Which is kinda the point. Yes, the more intellectual and electronic the world becomes, the more schoolchildren need something like PE to remind them that they have a body for a reason, and it does in fact respond to what you do with it. And yes, the problem is very much one of management.
I don't know where all these stories about self-defense classes and stuff come from, because my schools were definitely in the "fat guy with a whistle pointlessly yelling at everyone" camp. My 7th grade PE coach took it a step farther, in that he was active participant in whatever the day's activity was. By inevitably putting to together teams, one of all the 9th grade guys whose grades got them kicked off the football team, which he would captain, and the other team made of everyone else, "captained" by me, who would tackle dummies, whether or not the game was football. If he was hung over or had too much homework from his other classes to grade (my district had a policy of using coaches with a free period to teach other classes like basic math and history, because who needs a degree, right?) he would just tell us to run around and stay busy. The semester final exams were to play against him in GoldenEye, with your grade based on how well you do.
It was abundantly obvious that this was a guy who never got over the fact that gradeschool ended, so he got a job that let him bully middleschoolers for the rest of his life. And I'm not just whining about being picked on or anything. After a few months, I was sick of him increasingly singling me out, so I went to the vice-principle about it. This got me singled out more. I was his caddy, his demonstration dummy, his mascot, and at one point a human football. After a while, I just stopped giving a shit, at which point he lost interest and stopped as well.
Since I was in the band, I never had to go to PE after 7th grade. After I quit the band in high school, I had to pick trimesters of physical stuff. That would up being two trimesters of off-campus bowling, and one of tennis, which was only because you couldn't take only bowling. And tennis wound up being what the long-suffering coach called "abstract sports", i.e. running all over the court and talking videogames between serves.