alt Hacker Newser.. no - I've been a daily user of Photoshop since '98 or so, but after getting annoyed with Adobe's subscription model a few years back I bought Affinity Photo and looked to move over entirely to that, yet I ended up back in Photoshop purely because of literal decades of muscle memory meant that every interaction that I had with Affinity's offering came with an undesirable cognitive speedbump.
I'm not a fan of Gimp (haven't given it a shot in over a decade, to be fair) but if it covers the basic capabilities of PS and provides for an almost straight swap for users looking to change, then it is literally the layout and shortcuts that will be the decider for them.
Seems like you're actually agreeing. What you're attached to is all the work you put into learning Photoshop, not the particular UI of Photoshop. Learning GIMP is throwing hundreds or thousands of hours of work into the trash. IMO, learning GIMP is going to be a lot easier, though, because it's logically organized - it's easy to guess where things will be.
That's always going to be a problem with switching from anything to anything other than a clone. I can't play superior, I'm still clinging to MATE for goodness's sake, but at least I know I'm being dumb and have plans to move.