This is your experience, your preference, and your prerogative. I appreciate your sharing it, with your characteristic eloquence. However, I don't completely share your take on it.

I work just fine with people I've never broken bread with. I can also totally enjoy sharing a meal with someone I'd never want to work with.

I can, and have, worked very well with people I've never even met.

I agree that you can learn a lot about a person by observing them when they're not "performing."

However, I can work with someone perfectly well who I would not care to spend non-work time with.

As long as we're both professionals with a shared work goal, I don't care if they're a self-absorbed person on their own time.

A caveat to that is that there are some behaviors that are so antithetical to my world-view, that if I find out a person is like that, I'd avoid working with them even if they don't behave that way toward me or in my presence.