You go to a Apple, Google or Microsoft conference, GUI programming talks are about how to implement good UI/UX and take the best advantage of their tools for UI development, usually with workflow exemples from concept up to final product.

Most GUI tracks on GNU/Linux conferences are about low level details how to make certain drivers work, ongoing XWindows refactorings, or refactorings on GUI libraries.

So it is clear which tech do eventually GUI focused developers go to.