Overall I agree with everything you’ve said and I also use ChatGPT and Claude directly. The issue is that:

Good at integrating AI into a text editor != Good at building an IDE.

I worry about the ability for some of these VSCode forks to actually maintain a fork and again, I greatly prefer the power of IDEA. I’ll switch if it becomes necessary, but right now the lack of deep AI integration is not compelling enough to switch since I still have ways of using AI directly (and I have Copilot).