I may have found a way to make it work: try to launch it via terminal using admin privileges like sudo xed . and next time you launch it should magically start. I previously cleaned everything under ~/Library/Develop and tried without success from /Library/Develop (with admin privileges), I also previously deleted and reinstalled Xcode from the AppStore a couple of times. Once it started I removed all previously installed iOS and watchOS simulators that thought I removed before but instead they were still listed as "installed" by Xcode > components, because I think what caused the issue were those components that were probably corrupted by the latests macOS and/or Xcode 26.4.1 update.

I'm having exactly the same issue.