Are "nice guys" really unpopular? .ask

Not someone who is just "unable to be bad"
Not a pushover
Not someone who just "became" nice
Not someone whose true bad nature comes out once they get power
Not someone called nice just because they have nothing else to say
Not any of those various versions of "nice"
I mean a man who is truly, genuinely "kind-hearted."
I feel like a man like this would be quite popular with women,
but are men like this really unpopular?
(I'm not talking about myself. I'm not a nice person by any standard.)