My Mac Mini crashed and restarted, and the SDKs are all broken again. I am going to have to spend another hour with SIP etc to get this working. Can Apple acknowledge this is a real issue they are working on resolving please? It's an intolerable situation.

As diniska wrote, this is what finally worked for me: Force quit Xcode rm /Library/Developer/CoreSimulator/Images/images.plist Wait 1-2 minutes Launch Xcode You do need to reboot in recovery, turn off SIP, do the deletion, reboot in recovery, turn on SIP, and reboot. But it's been working ever since.

The latest Xcode Beta does not work either. Hangs almost immediately.

xcrun simctl list just hangs for me. I found my Intel based Mac Pro still works with the same set-up. One of my Apple Silicon Mac minis sort of works, one does not no matter what I try.