It's a bit of both of course, but I'd say mostly the latter.
As you point out, Youtube can make Flash apps that don't kill your cpu, and so can I and many other people. But there's a ton of developers out there for whom Flash is just too flexible.
There's been a big backlash recently against Flash, mostly I feel by people who have never actually done any Flash work. Having done plenty of it myself, here's my opinion - for what it's worth: If we ever manage to get rid of Flash, it will be because browsers finally catch up and do all of the things that Flash does, with the same amount of flexibility. That will be good, because the standards and most of the implementations will be open. But it won't fix the problem of spinning fans. The same bad developers who are currently making your fans spin with Flash will just move on and do the exact same things in javascript.
As you point out, Youtube can make Flash apps that don't kill your cpu, and so can I and many other people. But there's a ton of developers out there for whom Flash is just too flexible.
There's been a big backlash recently against Flash, mostly I feel by people who have never actually done any Flash work. Having done plenty of it myself, here's my opinion - for what it's worth: If we ever manage to get rid of Flash, it will be because browsers finally catch up and do all of the things that Flash does, with the same amount of flexibility. That will be good, because the standards and most of the implementations will be open. But it won't fix the problem of spinning fans. The same bad developers who are currently making your fans spin with Flash will just move on and do the exact same things in javascript.