It is valid.
Doesn't look like it from here.
Full CMYK support (Gimp finally got a working version last year and it still has a bit of work to do to get it to Photoshop's quality)
I don't know why CMYK support might be important but this seems to be the only technical concern and you've stated that GIMP has working versions with support. shrug
Working with Raw and PSD files. Tight integration with other software to be updated 1:1 without saving and loading a file.
This isn't about design, this is about interoperability. You're just talking about network effects, nothing to do with the software itself.
It's really not reasonable to say "just move to gimp."
That's not what I said. What I said was: it's not reasonable to say you can't earn a living as a professional designer using GIMP.
when specifically the OP said, "these do not work for the industry I am in." So respect that.
But I know people in the design industry who use GIMP, that's the whole point. I don't respect what OP is saying about that because it contradicts my experience. I respect my own experience much more than other people's words. Especially when they seem to be woefully uninformed.
I don't understand this analogy. Why does capitalism have a gun but communism doesn't?