It's a double-edged sword. I get why some apps say, "I want to handle everything myself", because then you don't have to debug which versions of a framework you're compatible with, and you don't have deal with these massive layers of abstractions. I hate working with frameworks, if I was building a Linux app I would be very tempted to just directly call into X or Wayland.

On the other hand, the last time I launched Braid on Linux, I had to manually change my resolution back afterwards and it removed my desktop background.

And I just felt like, "I'm sure there was a really good, sensible reason for whatever hack this game relied on when it originally launched on Linux. But... come on, if you had used some common framework, for all of the terrible problems that might have brought, when I launched it years later it would have at least full-screened properly."

So I dunno. The number of really big Linux apps that end up using their own custom display code is surprising to me. Even Emacs isn't fully using GTK. I assume developers of those apps are smart, so I assume there must be a good reason for it.