But why can't you be both an outstanding engineer and a friendly-and-approachable team player? BUT WHY?!?

Actually, the two requirements are completely unrelated to each other on an individual basis.
But chances are, that good team players prefer jobs having more human-to-human interactions...

If one engineer is being seen as "outstanding" - there's a great chance he is just GOOD, but those who observe him as "outstanding" are simply bad engineers.

Then after some time (months, years) the GOOD engineer has just his/her limits reached and can't handle bullshit anymore.

Happens 4 out of 5 cases (own observations, myself included).