This is going to sound silly, but I think a part of it is people are a little attracted to him.
HEAR ME OUT ON THIS! I'm speaking from experience in multiple fandoms, because it happens all the time.
The same thing happened with Professor Membrane in the Invader Zim fandom. Professor Membrane is a HORRIBLE father. He torments his own son by regularly calling him insane, refusing to be supportive unless Dib does something Membrane likes, allowed his son to be drug into an asylum despite knowing the cause of Dib's symptoms in that episode, and was almost completely absent from his children's lives, depending on machines to raise them. The only people trying to paint him as a good Dad are people who find him attractive.
Now let's look at Triton who, despite his age is way more conventionally attractive, swims around topless, and is a fictional creature that is frequently depicted as desireable
(Yes, the bottom right one is official Disney art, Triton's Kingdom by Jared Franco, and it's expensive)
A lot of people view Triton as a DILF. A lot of them are the same people saying he wasn't that bad.
People in fandoms have a history of defending characters who were obviously in the wrong if they also happen to be attractive to them.
Common examples include Loki before he was redeemed, Killmonger, Sephiroth, Mother Gothel as portrayed in Tangled (the amount of people I see who actually argue she truly loved Rapunzel is horrifying), Severus Snape, Draco Malfoy, Ursula, reboot Catra who continues to abuse She-Ra even after her supposed redemption, Lusamine (by the Pokemon Company themselves no less!), etc.
It's more obvious with villains, but it definitely applies to King Triton, too.
I think part of it is no one wants to admit they find someone who's clearly not a great person attractive. They're fictional characters, not real life criminals. Be all right with saying, "Yeah, this character isn't a good person, but I still think they're hot" and move on instead of trying to defend everything they did. Or if you wanna go the extra mile, write them a little redemption arc that fully acknowledges they did crappy things.
jbbartram-illu
theartofmadeline
turnnoffyourmind
gummygunk
