I’m a Zoro fan and I love Shanks and Kata.
I don’t like Sanji but also don’t hate him. This has nothing to do with being a Zoro fan.
I don’t love a character because of his strength, it’s just a nice extra. I don’t care who’s stronger than Zoro, I love him because he’s loyal, badass, has will power, a leader/right hand etc.
Every fan base has idiots and great people. There are some Sanji Fans I dislike and some really nice ones. They’re also toxic Sanji fans or Sanji fans who want a Zoro 2.0.
Theres are people who say that Luffy = Zoro/Zoro > Luffy but also people who say Zoro/Sanji and Sanji > Zoro. They’re all trolling each other. I also troll Sanji sometimes, just for fun. They’re also toxic Luffy fans who think that Luffy and Oda are perfect and it’s forbidden to criticise them.
Zoro fans are always the "bad ones" but every fanbase has such people.