It’s all about defining the “in-group” to exclude people they don’t like. It starts with not liking the person, then looking for a behaviour they can call “not masculine/feminine” because the worst thing you can be is not representative of your gender.

No one has ever said that drinking a milkshake with a straw is unmanly. But Tim Walz did it, and we don’t like Tim Walz, and if the out-group does it then it must be bad.

This is also why calling them “weird” bothers them so much. “Weird” means you’re part of the out-group. However, the average person doesn’t exist, everyone has something they do that the average person doesn’t. You tell a person without an in-group out-group obsession that something they do is “weird” and they won’t care and continue enjoying their life. Someone who is obsessed with being part of the in-group will feel ashamed about not being average and try to hide it. It’s an impossible standard they expect out of themselves and everyone around them.

Also, isn’t obsessing over how a man drinks his milkshake with a straw kind of weird?