Seinfeld the series was born in the late 80s and grew up during the 90's. Sad to say, Jerry did not. Jerry was the embodiment of the 80s 'me' mentality. Jerry's motivations are rarely if ever altruistic; even when he buys his father a new car, he does it to be 'the good son'. His only serious relationship (or so it appears) falters because in a rare moment of insight, Jerry realizes he has projected himself into his fiance. Some part of him realizes his dichotomy; narcissism *and* self-loathing...he only 'loves' her because she is so much like him, but then he dislikes her for the same reason. Jerry is not demonstrable in his affection....well OK there was the 'smoochy' episode...but towards his friends and immediate family, there is a definite reluctance to embrace.
His redeeming feature is his generosity. He allows the freeloaders to come and go as they please though his apartment, eating his food and borrowing his property...knowing full well that he probably won't see it again. When George and Kramer in different episodes effectively destroy his car, his attitude is initial grief and almost immediate acceptance.
Of all the Seinfeld characters, Jerry himself is the one I find most difficult to like. Jerry himself would probably not be bothered by this opinion at all...he's not taking any more applications for new friends, is he? ;>
Peter