Adobe’s UI is also terrible, but it’s terrible in a way most digital artists are familiar with. Starting from scratch Gimp, Inkscape, and Adobe have reasonably similar learning curves.
The main advantage Adobe UI has is many people assume they’re stuck learning it at some point. But it’s definitely a waste of time and money if you’re happy as a hobbyist.
Adobe doesn't count hobbyists as a core user segment; why would they? Hobbyists don't need Adobe CC any more than somebody looking to multiply 2 numbers would need Excel 365.
The hobbyist market is already served by Photopea, Canva, Snapseed and many others.
The main advantage Adobe UI has is many people assume they’re stuck learning it at some point. But it’s definitely a waste of time and money if you’re happy as a hobbyist.