Basically everything I've tried has worked on my Apple Silicon Mac, including x86_64 Docker containers using Docker Desktop. I'm sure there are applications that don't work, but I've yet to run into one first hand and I'm a software dev.
In retrospect we probably should have forced all devs to switch to M1 at once and upgraded everyone’s laptop, but we saw all these posts about how everything works on M1 and that just wasn’t the case at all in our experience.
Our software at work didn't work out of the box on M1, but fixing it was fairly trivial and mostly involved upgrading library versions (although we use Node not Python which admittedly tends to be better at portability). But someone completely new to the codebase definitely isn't the person to be fixing these issues.