Well, his audience is "serious" / professional musicians (= getting a degree and doing this for a living). Keep this in mind.
Even professional life has become much more diverse for "working musicians" than it used to be.
As a counterexample for a "professional musician" today, this might be interesting (Steam Dev days lecture)
Besides some fairly epic computer games music
(OK, this one's matter of taste) this guy
is actually doing visual effects (3x Hobbit, 2x Matrix).
The point? That specializing 5 working years of your life on piano playing alone isn't necessarily the smoothest start into a professional career those days, will it pay off?
And the "less" serious folks can have fun playing music disregarding 90 % of what he's saying.
When you don't practice 15+ hours per week, what's the point in being equally bad in all keys? Start with the three that you'll actually need (like, C because it's easy, E and A, D because guitar players like those or the "horny" equivalent for your brass section if that's your thing).
Same with sight reading. You may know right from the start that you'll never need it, then it's a huge waste of time that could be spent more productively training your ears
instead (for example).
With recording, he's spot on. It kills illusions, but constructively.