While so many things are so much better than they used to be in the programming ecosystem, I feel like entry-level GUI programming is so much worse.
This will probably be an unpopular opinion, but Visual Basic (pre .NET) was one of the easiest ways to make a simple, contemporary (for the time) GUI. Drag and drop some elements, modify the UI properties, double click and add code. It made for an excellent introduction to programming because the UI portions were simple and intuitive enough to stay out of the way.
The rest of VB wasn't great. Weird language/syntax/keywords keywords, closed environment, mediocre tooling. But for building UIs? I haven't used anything as easy as that and it's been over 20 years now...
I don't have any recommendations unfortunately. Almost everything I do is web based or command line. Web UIs aren't terrible, but there's a learning curve and lots of limitations. Haven't found anything for desktop apps I like lately (last one I built was also with tkinter for a small Python project. Bleh.)