I'm not a frequent user of Photoshop, so I was wondering what it does that Krita doesn't? (Or gimp)
The efficiency of these tools is not measured by the capabilities, but by the effort it takes from the user to get the expected end result.
It's Photoshop I can't replace with something else.
I think this is the biggest problem with FOSS alternatives, and it's a people problem (the type of problem FOSS devs are rarely equipped to solve). It doesn't matter what the technical merits of Krita or Blender or whatever are, because the same complaints from the same people will never go away. The only reasonable way forward is to ignore that demographic of people and their complaints, and just focus on doing their own thing.
This isn't a new phenomenon, it has always been this way. If you're a professional who uses Photoshop in their daily work, consider that maybe your assessment of FOSS alternatives isn't fair, and try dedicating some time to learning a new workflow with new tools with an open mind. If you're not willing to do that much, then you're going to be stuck with Adobe forever, and will be forever grouchy.
Sure, if they don't want to have users.
If you think folks haven't done this, then you're not paying attention. They've tried that and failed. That's the whole problem, they're failing to migrate to the open source options. That we can just take as a given, look if you can't compete with Adobe in 2024, then you're not ready to be at the table yet. There have never been better conditions to compete in these areas than there are right now.
Note that none of your complaints hold up with Blender, sure I occasionally see folks suggest that Blender's UI is a bit janky. But the overwhelming sentiment in creative circles toward Blender is heartfelt gratitude that application exists and is so capable. From my own personal observations, I'd put Blender as one of the most loved GUI applications in existence today.
I'd even go as far as to say Blender is over loved, I don't think it gets enough pushback for not having a dedicated GPU-renderer which is tablestakes feature today. So I'd actual say your entire point is actually inversed, FOSS gets too much leeway for being less capable because folks value the FOSS (and free-as-in-beer) points too much, which causes the software to be recommended in contexts where it really shouldn't be yet.
(Note: I'm not a 3d professional, though I am somewhat connected to it. I am mostly observing the community from the outside, so if I'm wrong about this I'll welcome the correction.)
It's an open source near perfect clone of photoshop