Fantastic rundown, thank you!
Wow I missed canvas support completely. This is going to make some custom UI's way easier to make compared to the hacks I had to resort to in the past [0]
I do hope one day we'd get a new cross platform performant display engine that draws like Zed does for more UI capabilities in Emacs. Neomacs[1] promises this and has some of this but looks like its suffering from never ending scope creep and continuously moving back and forth between 80% there and 90% there due to unattended agents running wild.