Lightroom Classic v11.5 Crashes on MacOS Catalina 10.15.7

Hallo,
bei mir hat geholfen die Berechtigung in dem Ordner
/users /xxxx/Library/Logs/Adobe/
auf schreiben und Lesen für Staff und everyone zu ändern!
 https://support.apple.com/kb/ph25287 

If resetting preferences doesn't work (it very often does), try logging into another Mac user account (you should make a new one); still crashing? 
Try starting up in Safe mode (hold down Shift Key when booting*), still crashing? 

The first thing that you should try is to switch off the GPU support from the Lightroom preferences and check if that helps to fix the issue.

Go to Lightroom > Preferences > Performance tab > Uncheck "Use Graphics Processor" > Restart Lightroom.

https://helpx.adobe.com/lightroom-classic/kb/troubleshoot-gpu.html

If Lightroom doesn't start correctly the please see "Solution 2" in the document behind the link below.

Troubleshoot GPU issues | Lightroom Classic (adobe.com)

Another step is to try to reset the Lightroom preferences.

https://www.lightroomqueen.com/how-do-i-reset-lightrooms-preferences/

It's recommended to backup your preferences before you reset the preferences to the default settings:

https://helpx.adobe.com/lightroom-classic/kb/preference-file-and-other-file-locations.html

If this doesn't help we need more informations about your environment.

Please provide also a copy of your 'System Info'. This can be get from the LrC Help > System Info menu item. There's a copy button in the System Info dialog. Press this button and paste the info into your next forum post.