On macOS applications usually reopen the last documents you were working on. If one of those has a problem you can start the application opening, and immediately hold down Shift, to stop it from reopening the documents. That may be worth a try.
The welcome screen loads recent document thumbnails, if there is a thumbnail issue I can see that could cause a problem. There is a way to avoid showing the welcome screen, by editing the preferences file. Or you could right-click on an old trustworthy SKP, and open the file that way. Then the welcome screen shouldn’t show.
I do all of my M3 testing in macOS 15.2, and don’t think that will be the cause of the problem.