Is this a new form of gatekeeping?
I.e., "too human-friendly to survive in the presence of The Great AI™".
If so, where does that lead us?
These libraries are not more human friendly. Humans can write GTK or win32 or QT or Cocoa code just fine. GUI frameworks are very complex and often have very in depth setup code that is required. It requires a huge investment to get an app up and running with a GUI framework, and AI makes setting that up approachable when it was a real challenge before.
Have you ever written GUI code using one of the big GUI frameworks?
That's an aggressively negative over-interpretation of OP. Clearly not what was meant.