[2022] Stellaris crash upon game opening (Mac)

Note that the Apple M1/M2 platform is not supported hardware for this game, only Intel/AMD CPUs are. Which may or may not be related to your problem, but does limit what we can do here.

Does this just affect that one save file you mention, or any other one or new test one you might start?

If just the one, was it started under current game patches, or earlier ones?  

If that save you mention reliably triggers this crash, please make a new thread in Bug Reports and attach it there, for QA to look into.

Sorry for that problem!