Wayland seems ready to me but the main problem that many programs are not configured / compiled to support it. Why is that? I know it's not easy as "Wayland support? Yes" (but in many cases adding a flag is enough but maybe it's not a perfect support). What am I missing? Even Blender says if it fails to use Wayland it will use X11.
When Wayland is detected, it is the preferred system, otherwise X11 will be used
Wayland "leaves blind users behind" due to its security oriented design. A protocol or portal of some kind is going to need to be created to solve this problem, but progress here is severely lacking.
Not an expert, not an insider. Just commenting to inform about what i know.
When wayland was designed, security was a concern and it was handled differently than in X decades ago. That is good.
Under X any application can be a screenreader and see your data. This was okay when you trusted everything on your machine, but is a problem today.
Under wayland's original design, no application could be a screenreader. That's bad. It took way too long to agree on how to make exceptions to the rule, e.g. for screen readers, screen sharing in video calls, etc.
Also out of the loop, but my guess is that Wayland hasn't defined a specific API for the purpose yet, and their security model doesn't allow programs to see the content of other programs' windows. X11 doesn't attempt to keep programs from seeing what other programs put on screen, so no specific API is needed there.