Flash Sucks

But everything else sucks more.

Where is the alternative to the write-once run-anywhere platform that has a rich UI toolkit, is installed on almost all machines ... what? Java you say? Really, come now; Loading anything in Java in the browser feels like I'm booting up a Virtual Machine. What about Silverlight? No, not that either.
Standards you say? Ok, let's roll. You can do most of what Flash does with:

1. CSS3
2. HTML Video
3. WebGL
4. Adaptive Bitrate Streaming (progress)
5. HTML Canvas
6. Imaginary Partial Loading Support That Doesn't Exist (maybe the partially supported <script defer="defer">)
7. SVG
8. The Imaginary Sandboxing for Separation of Applications standard
9. HTML Audio
10. HTTPS
11. WebSockets
12. Imaginary Crossdomain.xml Equivalent That Doesn't Exist
13. LocalStorage
14. ECMAScript 5
15. IndexedDB

And even if you got the imaginary things working and the drafts finalized you still need a solution that

• Works on all major platforms
• Works on all major browsers
• Has no nuanced implementation details
• Has non-conflicting, non-ambiguous standards
• Is well understood
• Has a usable IDE for graphic designers
• Has a wide, cheap, coder base.

Flash does this. In fact, I had streaming, synchronized, animation and audio in 1996, on Netscape 2.0, on a Pentium 1 @ 120Mhz with 16MB of RAM, on a 28.8Kbps connection, on Windows 95. All I had to do was download a 160KB add-on and restart my browser; back before DOM 0, and when the W3C was moving from SGML to the fancy new "XML" standard.
A decade and a half later, going to the CSS3 equivalent I have to carefully choose the browser, then see my cpu hosed and still have frame drop, have audio sync problems, and have to load ALL of it before seeing ANY of it.
The Flash hate is totally misplaced. What they have done is absolutely phenomenal. I'm sorry that you see teeth whitening ads and porno site popups with it, but don't blame the technologists; that's like blaming Honda Of Japan because some asshole cut you off on the Freeway.
And besides, what will the ad-haters use in this future world of 2022? Some amalgamated FlashBlock equivalent that can easily just turn off all the annoying stuff? This line will be blurred and it won't be possible.
Adobe has done, and continues to do what Microsoft Failed at, what Apple Failed at, what Sun Failed at, and what Google is almost, but not quite, succeeding in, decades later.