You are qualifying a boxing fan's dislike of Canelo on the premise and tense of your question. It's not just some of his match-making in the present as, let's be honest, COVID isn't helping anybody so I don't hold that against him. His past shows that most of his best wins WERE against faded opponents. That's not really convincing neutral fans who like the sport. Several of his best wins: Lara and GGG x2 arguably aren't REAL wins in the eyes of a startling number of people. Basically every top win except Trout, Lara, and Jacobs is against a guy on the downslope of his prime. Lara and Trout, to me are his BEST wins because those guys were actually at the top of their game and were legit threats at the time of the fight.
In summation, any dislike they have is rooted in the past and therefore they hold the present suspect until they are proven wrong. CoVID is jamming things up a lot. Canelo will really need some big fights without asterisks to change the opinion of said "haters," and that won't be easy because of his history and usage of PEDs and the judging that gives him the benefit of the doubt of every close round.
more than ANYTHING, because of those things, Canelo has created a fan gap for himself that won't be bridged. He will never get universal respect or acclaim because of who he is.
I'm in the middle. He has made some good fights and has real talent and he went after two guys (Trout and Lara) that nobody wanted to touch, but he's also a filthy cheater who is awarded rounds he has no business winning, and I just don't respect that.