Famous people say a lot of things and any random advice coming from an authoritative figure is not guaranted to be insightful. On top of that quotes are massively taken out of context and misattributed (this one probably is)
That to me makes the whole quoting one liners format useless if the quote doesn't stand on its own(except when it's used ironically?)
Not to mention that giving people credit is always laudable and should be done much more, not less.