It doesn't mean it's actually useful advice for someone who wants to get ahead.
Clearly, some jobs teach you more than others...
My criticism has everything to do with his use of "career" where he should have said "skills" or "personal development" and his use of "years", when time spent has absolutely no objective relevance, as reinforced by your own comment: 1 year at firm A is not equivalent to 1 year at firm B.
So the implication that there's an objective salary advancement/year or career advancement/year rate is nonsense. It's detritus from the failed management schemes of an older era.