Forgive my ignorance, but what should happen here? Let say I have a scrollable text pane with an entire novel in it.
I agree there should still be a mechanism to pass more accessibility data than OCR could extract. What is the bare minimum information that is required? Pretend there is no UX model -- arbitrary things could be presented (like in a video game).
In particular, with Gio there isn't necessarily a single set of widgets or UX. Gio has a small set of Material Design compliant widgets, but is mostly a library for composing immediate mode graphics. For example I have several custom widgets, some that only interact with the keyboard, some that don't have any text at all (just graphics or animations), one is a akin to a 2D-scrollable map, click-to-drag Google maps style. I'm not really sure where I'd begin in making these accessible. How should something like Google Earth be made accessible, ideally?
https://machinelearning.apple.com/research/creating-accessib...
Just IMO, it's unrealistic to expect to have an accessible GUI that stores no state, does none of that type of bookkeeping, has no OOP model, and only outputs to pixels. The point with these type of assistive technologies is that the user can't work with that type of visual data, they need more state presented to them. Sure, it makes everything easier to develop when you cut it all out and only use immediate mode, but that's exactly the problem: everything else has been cut out, on purpose.