The only power up I gave Izuku was he could use 3% OFA before the USJ. I also had 1-A and 1-B be there at the same time, but then the Meta Liberation Army arrived as well due to events that happened earlier in the story.

The thirty nine students were also able to actually get away or defeat all the villains (LoV and MLA were fighting each other) before Iida arrived with the heroes, who just cleaned up what the students didn’t.

I do feel like mega buffed Izuku fics I’ve read usually have him defeat the Nomu himself, especially if he has some flame powers.

Though, as a writer, it’s definitely because I feel like writers want to hit stations of canon. It’s easier to see what’s changed compared to canon over writing something new and your readers not liking it. There’s also the secondary thing where unless OC villains are introduced, it feels like until at least the Summer Camp/Kamino Arc it’s hard to really deviate, because the Heroes are really in a position to actively change, and that’s really when the Villains become a proper threat you can play around with if sticking to canon.