You can like Canon and Fanon
I love canon, I love canon a lot. I love Jily, I love Remadora, I love Sirius' faults. But loving a character/finding them interesting is NOT the same thing as condoning their actions.
At the same time, I also really like wolfstar as a pairing, whatever rendition of it we end up it. I don't personally love the way it is commonly depicted/fanon version of their relationship where the core of it is changed, but I do love the ship.
Ik that it's not canon, I have never once proclaimed it to be canon, never will. Ik that they are like brothers in canon and I like that too. I just think that there are elements that can make their relationship really interesting and that me wanting to tweak the story slightly while keeping their canon personalities isn't wrong.
The problem arises when people on purpose deny canon and proclaim fanon to be canon. But if people aren't delusional, then let them believe what they want.