Don't know about the other links you've posted, but for photocraft the vast majority of those issues are from the engine that process the image itself, not about the GUI. In fact, as far as I can tell, none of the artcraft apps are that complex in terms of GUI to be slow down by any choice of GUI framework really. There could be performance differences between them, yes, but not so much.
Why are you stating something that is not true as though it were a given, and then using that unearned precondition as the basis for your question? The premise is false. Artcraft is a complete fucking trainwreck, nothing more than scamware that falls apart as soon as you poke beyond the deceptive facade that was used to build hype.
(That said, on the scale of blame for it being bad, I would say the GUI framework accounts for 0% of that and the programming methodology accounts for 100% of that)
UI for CAD-style apps is not that complex. You're typically looking at maybe hundreds of visible controls at most. Of course, assuming that the rendering of the picture/parts is handled separately.
Well, primarily users of Adobe software don't have efficiency in mind as their first priority. It's a little different if you are making a desktop widget and it eats a good chunk of your GPU while idle.
Most of these GUI software are vibe coded so state management essentially becomes somebody else's blackbox problem.
Can't you fix this scaling by chunking the entities? So not making one massive 10,000 thing entity but instead breaking it up into entities that group 500 things?
Why do those complex Adobe clones work so well then?
Slow, laggy UI is a common source of complaint on the issues.
Examples:
https://github.com/storytold/cadcraft/issues/752
https://github.com/storytold/cadcraft/issues/874
https://github.com/storytold/vectorcraft/issues/2292
https://github.com/storytold/artcraft/issues/2409
https://github.com/storytold/photocraft/issues/9327
(That said, on the scale of blame for it being bad, I would say the GUI framework accounts for 0% of that and the programming methodology accounts for 100% of that)
Something about every complex GUI being a spreadsheet-style calculation.
Most of these GUI software are vibe coded so state management essentially becomes somebody else's blackbox problem.