I see what you mean. I think I was the asshole friend because I literally only have 2 or so left now, aged 34.
Is it that the assholes are friends you’ve brought with you from the past? Long since parted ways in opinion, values, views but with too many shared experiences to want to let it go? Or possibly they’re just assholes you’ve grown to respect simply because telling mutual friends why you think they’re an asshole would be a risky and awkward thing, and you’ve subsequently spent a lot of time with them?