I agree, and the lack of empathy around this area is sad. If you're developing an app, it is better to fall into the pit of success by using a UI framework that already has accessibility baked in. Any project that uses Dear Imgui for end-user applications has already made a bad design choice. AccessKit (https://accesskit.dev/) seems to be a positive step forward, with some UI frameworks implemented (including immediate mode egui).
It's supposed to be a _tiny_ library. Naturally its capabilities will tend towards being minimal. I don't expect decent RTL language support, for example, although it's quite important if those are the languages where you live.
As for linking to something written in Rust with bindings etc. - that is the opposite of tiny when you consider the dependencies, and it would not be portable to weaker or older systems.