> How easy would it be to create a Flash product competing with Adobe's current online offerings back then it Flash existed?They did, Silverlight was it. MS pushed it as hard as they could, and... it bombed. Because it had the same problems as Flash, which most developers already reviled: it produced proprietary, black-box binary blobs that only one vendor knew how to run properly, and it presented big security and performance challenges.
Meanwhile, plain old html was something that everyone could work with, as long as the spec was public. The browser had a hard sandbox and very well-delimited capabilities. And that worked just fine, before Chrome ate the marketshare (thanks in no small part to Mozilla losing the plot, chasing ghosts in the OS space while Firefox floundered).
> Why has HTML5 turned out to be such a horrible after more than a decade?
Because shit is hard and browsers have different priorities.
> I'm amazed about the kind of economic blindness
Says the one with a broken website.