I agree with almost everything you said, except that RSS was never as popular as Twitter is now. Copying and pasting a URL is too technical, and Live Bookmarks were the wrong UX all around. Mailing lists are still more popular than RSS ever was.
In retrospect, if Firefox had used a New Tab Page with an RSS driven feed like what they do with Pocket now, we'd probably still be using it today. Too bad 2005 Mozilla didn't have UX designers calling the shots.
Do you have any examples of these things taking place in reality or is it just "possible" stuff. And Google did not kill RSS lol, it was always super niche.
Potentially, yes. Google abuses their search monopoly and ads duopoly to kill off competition in other areas.
They use their browser control to control internet standards.
They do things like effectively kill RSS via EEE style tactics.