Bruce Lawson is dead-on with his critique of Apple’s feedback on Web Components:
Implementation is hard. Too hard for the developers at Apple, it appears. So Web developers must faff around adding ARIA and tab index and keyboard listeners (so most won’t) and the inevitable consequence of making accessibility hard is that assistive technology users will suffer.
We (browser makers and web developers) need to be willing to put in the effort to make things better for everyone else. Sadly, few seem interested.
Thanks for calling this out Bruce!