It turns out they were right. The whole time. Assholes. I’ve been doing a pretty consistent midnight to 9-9:30 for a couple of months, no screens in my bedroom, just a nightly podcast. And I’m usually asleep inside half an hour. Sometimes well inside. I still sometimes wake up during the night but that’s mainly cos of painful crampy legs from working on my feet all day.
I regret to report that sleep hygiene is in fact a thing.
I have the same problem. I used to put on a movie I found soothing and knew well enough to not keep me awake wondering what would happen next, but the light from the screen wasn't great, so I switched t audiobooks. I have audio editions of several books I've loved since childhood, so they make me feel cozy and keep my brain engaged enough that it won't decide to entertain me with weird bullshit and keep me awake, while not being a new story that's going to keep me awake wondering what happens next. I have no idea if this will work for anyone besides myself, but it might be worth a shot.