I think HLS is pretty awesome and this hasn't anything to do with HTML5 as what Chrome supports doesn't allow for live streaming, which is why sites like Twitch still use flash for Chrome. Chrome should support HLS, but they aren't going to for anything but Android, so flash it is for the foreseeable future. If anyone knows why or where I am mistaken I would like to know.
The issue is not black and white. Why should Chrome implement Apple HLS, rather than Adobe HDS, Microsoft SmoothStreaming, or MPEG DASH, among other HTTP streaming formats? What about RTSP -- a protocol designed for streaming, which Android had good support for in the video tag?
In any case, live streaming in Chrome is possible with WebM, or even WebRTC. Flash is not ideal either, but at least it has consistent support on the desktop.
RTSP doesn't go through firewalls easily. That's pretty much why Apple invented HLS. It's a nice, minimalist solution to adaptive bitrates that uses standard HTTP to get the job done. Big players such as the BBC have adopted the standard (ugh, I'm writing a client for it right at the moment!), so it's not a particularly fair categorisation to label this as a purely Apple thing.
If it's possible why hasn't anyone implemented such a thing? I'd like to implement such a thing and I wouldn't know where to start, but I would with HLS. This is the 1990's all over again. Different browsers supporting different standards, different video encodings, different JavaScript features, sometimes, when I'm having a spell, I'm not so sure competition is actually all that great anymore.
And no you cannot stream with webrtc without building a complicated back end webrtc MCU implementation which requires significant engineering and is not at all supported by the creators of webrtc who are focused on peer to peer inside browsers.
In the 1990s, people used to write these things called plugins to add features, like support for specific video containers and codecs, to browsers. Now I guess browsers have to have everything built in or not at all. "Progress".