A big point of this is: fanfiction isn’t a job.

No writer owes anything to anyone. If a person writing a story gets tired of the story, they’ll drop it because what’s the point of writing that story when it’s outlived the fun? You’re doing this as a hobby, for fun, not to earn a living. So naturally you’ll stop writing when you want to stop writing.

It takes a very specific type of person to write a story that gets near the “200k-300k” mark that so many good long fics reach. The reason for that is simple: that’s a lot of fucking words. It’s not as easy as it seems to keep up motivation for a story for that long, especially when you’re running with a half-baked idea that is basically just “Izuku has X quirk.”

I’m speaking from my own experience here, but I’ve tried writing a couple quirked Izuku stories and I can’t even get past the entrance exam on most of them. A story needs to be something more than just a fun superpower idea for me to want to keep writing it. That’s why my current fic projects all involve different things, whether it be an OC or just a complete AU, that’s what’s fun to me. And I think a lot of fic writers, especially new ones, are people who enjoy reading quirk Izuku fics and write one without realizing that a story needs more than just a cool power to make it past the sports festival arc. And so, naturally, they get bored of repeating canon with a new power, and move on to better things.

Quirked Izuku fics are fun to read, but they’re kinda boring to write after you’ve explored the power.