flash was obsoleted because 1) iphone didn't support it, 2) iphone didn't support it, 3) iphone didn't support it, and 4) JS replaced the non-DRM use cases (and now even replaced that).

Well that and Flash was a massive vector of security problems.

Plus it wasn't very good on mobile, even when it was supported (ie - on Android it was still bad and never got out of beta anyhow)

I thought it was fine on Android, I played many games on it that worked well even on those old underpowered phones. It was never good, but probably about 0% of flash apps were written that targeted mobile so I wouldn't have the expectation of good.

I think "fine" is being generous.

When it worked it was... not great, due to UI issues, but it at least worked.

Trouble is it seemed to not consistently work. I worked at a flash game developer at the time (Zynga) and it would not always load our games even if it had done so previously - the difference was sometimes just refreshing a page.

May very well be the case. All things flash are permanently disabled on my browser. If a site requires flash, I would much rather ignore the content altogether no matter how juicy it is.

I did a lot of Flash/Flex work - it was the bees knees of front-end dev in the days before JQuery, Firebug, Chrome etc. and was the most consistent across platforms, as the same plugin was used on each, as opposed to trying to make your web-standards-based app work on several incompatible implementations. HTML/JS/CSS didn't come close at that time, but there was hope that it would develop to make Flash obsolete - which it now has.

People always complained about how Flash "drained batteries" / "crashed browser" / "allows all this intrusive advertising". A case of blaming the technology for the way it was being used. People would say "I can't wait until Flash dies and we have the open web standards instead so we don't have these problems any more".

So, fast forward a decade or so, Flash has been replaced by open web standards and ... guess what? We still have those problems...

Because designers keep trying to turn static pages into "interactive" glossy booklet emulators, never mind "app"...