Thank you all for the thoughtful replies. Sorry, I've been on quiet mode this last week and still mostly am :P I have been reading though.
I guess, I think, "nice" is an ambiguous term and can mean many things. I think some personality traits are hardwired in and some people get some traits that make being kind, generous, patient and those sorts of things easier than they may be for people with a different set of personality traits. I guess though, that acting kind, caring, patient, compassionate, respectful is a choice. That sometimes, for pretty much everyone those things will come easier, and sometimes, pretty much anyone will really have to put in effr to do act in those ways.
And I don't think nice should automatically be assumed to be insincere or fawning, but it can be those things. And the idea of fawning gets me all sorts of tangled/triggered and I talked to my T about that today. (Once she managed to get me talking)
And yes,
@Friday, I suppose the vice-versa must be true. That sometimes being an a-hole will come automatically to almost anyone, but if you are doing it consistently, you are making choices.
Blah. This whole topic tangles me knots.