As far as I can tell, Electron is the only cross-platform UI toolkit where it's even possible to get accessibility right on every OS.
At least for me, the story quite simply ends there. No, it's not the GUI toolkit I wish I had, but, if the goal is to develop for the 21st century, then I think that being accessible is the ethical choice. And, given the current tech landscape, that goal is satisfied by three options: Electron, developing three different native desktop GUIs, or deciding not to support less popular platforms.
I'd rather have UIs that are true to their platform (and all the nice little accoutrements that come with) than this universal, inconsistent crap that works OK at best