-Most art communities. The gatekeeping is so bad sometimes they can be outright hostile (like DA) if people don't adhere to the general groupthink. There's also bad moderation and lack of user interaction that just discourages newcomers who try to improve and reach out for help. Screw the mob mentality when those types just do so much mental damage to young starters. Being frank, no one cares for useless drama, so don't start it.
-Art tutorials. The ones that do the "draw like this". It seems restrictive and limiting. There's so many ways to draw things, and using someone's stylized art could be hindering when not going back to the old basics of studying real life. I also hate the advice of "practice drawing everyday", not counting for burnout.
-The old "you copied my character design" accusation. I don't need to explain this one, it speaks for itself why it's dumb. Unless it was blatantly ripped off, blowing hot air is just gonna make everyone hate you. This counts with the species thing too; it's not worth it throwing a fit if someone makes a personal character based on your species, maybe unless that person is claiming ownership and designing said species, but even then, don't go overboard.
-Many Adopt creators not understanding or thinking they still have a say in how that design they sold is used. Especially when it comes to letting the buyer sell how they want. Seriously, it ain't yours anymore. That's not how it works in the professional world, and it's entirely disrespectful to the buyer. If you don't like what someone's doing to something they bought, then don't sell to begin with. If you try to take back the design, then you're stepping into illegal territory.
-Closed Species MYOs. Those feel like straight up ripoffs to pay for designing something myself. I have a CS, and I don't do MYOs for sales cause I think it's a scam. Just open up for Customs.
-Also with the CS, restrictive rules where the buyer can't even do redesigns. Like, they own the design, you don't have a say if they redesign. If you don't want that, then just have a Cannon version and they can have a version of their own. Or lessen the paywall so people have a better chance to get what they want.