If I'm not mistaken the solution was to make touching an element trigger the :hover state and the click action unless the :hover state changed the visibility of another element. If the :hover state changed the visibility of another element, then the click action was not triggered until a user tapped again.

This is possible in HTML because it's trivial to determine whether or not a :hover changes display or visibility properties of other elements. As you've supposed, Flash did not afford browsers with that sort of ability.

> more affordances for accessibility than Flash ever did

TBF one thing Flash did manage to achieve was the proliferation of web sites and apps that were as hard to use for people without protected disabilities as for people who did have them.

Whether this increased empathy for people with disabilities is an open question