I have been trying to figure this out for years, Premiere Pro crashing on quit has been a problem for me on several different Mac and several operating systems. It reared its ugy head today as I made the mistake of doing a Big Sur update on my M1 Mac Mini running the latest Premiere. It even does this with the brand new M1 Premiere Beta. I have tried everything, reinstalling OS, uninstalling and reinstalling Premiere, changing location of cache files, etc etc. I know this problem has existed since at least 2013 - does anybody have any suggestions?
Also the M1 Mac Mini with 16GB Ram I have regularly runs out of application memory, regreting the purchase now. Apple has no answers.
Disregard my post from above. I just uninstalled and installed an older version of Premiere Pro (14.6) and now it runs beautifully with Big Sur 11.2.1 and no memory problems as of now. Also quiting is working now.