[unknown] I never looked at Go as a UI language
There really isn't a first-class GUI library for it yet. Fyne is probably the closest, but it's rough around the edges and the focus on Material Design is a bit off-putting for a lot of folks.
[unknown] I don't like GCs since I don't know what they're doing and when, feels like loosing control
Wasn't too long ago that this was the norm in C++ and Qt. Most of the time you don't need to worry about GC. A well-optimized GC like the one Go uses will mostly stay out of your way unless you are doing a stupid amount of alloc/dealloc, at which point what you are doing is almost guaranteed to be sub-optimal anyways. Go developers have adapted to this reality, so they focus on reusing memory wherever possible with simple techniques like buffers or avoiding pointer types (e.g. slice of structs instead of slice of pointers to structs).
[unknown] The choice of only supporting or even still going for X11 is interesting for a new DE, most try to get rid of X11 where they can and get a wayland compositor running. But well, X11 will be around .. some time still.
Depends on your goals. X11 is a pretty simple API and fairly portable across Linux or BSD environments. It also nets you immediate compatibility with other UI toolkits and applications. Wayland barely does anything on its own. Most of writing a compositor has nothing to do with graphics, as you have to supplement all the other things that X11 does in order to achieve something close to feature parity. If you want to write a desktop environment and not another compositor, X11 gets you 80% of the way there and lets you focus on the 20% that makes your DE unique.
