camera shows in safe mode only after big sur installation

I may have a solution for you- I had the same issue. Went through the whole apple support gauntlet, with no luck. SMC NVRAM resets, safe mode, new users, even reformatting and reinstalling on the HD. It had only worked for me in safe mode. I finally figured it out, though. Since the upgrade to Big Sur, some of my Quartz plugins were invalidated. Removing them from /Library/Graphics/Quartz\ Composer\ Plug-Ins/ immediately solved the issue for me upon relaunching. The only way I was able to figure this out was by filtering through the console log stream while launching the application. I recommend the same process for you if my exact solution doesn't help, it may even be a different conflicting plugin in a nearby directory.

Greetings, Trypappollo!

Welcome to Apple Support Communities! We understand your camera is only working in safe mode on your Mac. We'd like to help out so you can get back to using your camera again!

Since starting in safe mode, have you restarted your Mac, then tested the camera again? If not, go ahead and do this first.

Should the camera continue not to work, we recommend working through the suggested troubleshooting steps in the following support article:

If your built-in camera isn’t working on your Mac - Apple Support

If you're still unable to use the camera, Contact Apple Support for additional help.

All the best.