Maybe other apps are better, but my guess is that they just work harder at copying PhotoShop's UX whilst GIMP actively worked to innovate.
Remember too that PhotoShop itself is unintuitive and hard to learn.
That unintuitiveness is a mark of honor for Photoshop ("ooo, it's so powerful you have to take _classes_ to learn it!") and a mark of shame for GIMP ("ooo, those twits didn't clone PhotoShop, the fools! It's so hard to learn!")
Well GIMP innovated in the wrong way, you can put the steering wheel in the backseat of a car in the name of innovation but that doesn’t make it better. I honestly would rather use JavaScript and canvas over GIMP because it’s just more intuitive.
... but it has always been worth it for any normal person, IMO.
That said... PS's new AI tools might make GIMP no longer a viable option even for normies like me.