Zeptal bych se na fóru Adobe Lightroom Classic, nebo si rovnou přečti odpověď:

Here is the workaround for resolving the issue of Lightroom Classic 12.3 not launching on macOS:
Manually change the permissions on the following folders and on all the items in these folders to Read & Write for the current user, so that Adobe applications are able to write to these folders when opened or during use:

/Users/[user name]/Library/Logs/
/Users/[user name]/Library/Logs/Adobe/