"FWIW it never went away¹ and targets standards-based runtimes these days. "

I just tried Adobe Animate recently and nothing worked out of the box or like flash used to.

I basically had to tinker, until even basic animations somewhat worked.

And I even have quite some experience with EaselJS, the target framework, but that didn't helped much.

The power of flash was the ease of use - that is gone.