I sort of get your point. And my counterpoint is this:
If not me, then who?
Who else is going to stand up and say — no — no, junior developer just starting out, this isn’t what a user story is supposed to be.
Who else is going to stand up and say — no — no, junior developer, it isn’t good practice to deploy a new release that breaks your app on mobile and looks monumentally worse on desktop than the old version.
FCC is claiming to teach people how to program — and people fundamentally learn by emulating — and — someone has to say “no, don’t do it that way, it’s bad practice”.
Note: FCC never did anything to me. And, as I go through the speedrun, I fully intend to point out the good along with the bad. Thusfar, there’s just been more bad than good (thought the addition of the flexbox and grid sections was awesome).