I'm quite content with minimal human contact. I only really miss my daughter and wife and once in a blue moon some close friends or family.

But I absolutely can notice that I get kind of feral after long isolation periods, even in terms of language abilities -- but I only notice it when being with other people again, not while alone; while alone I feel much clearer as you said.

My point being what you feel about your cognitive processes/world might not be objective reality.