It's usually the other way around. The nazis slowly corrupt a community that consists mostly of one of their target groups, pushing out people who are aware of their dogwhistles because, well, they're clearly nazis, and is not going to recognize that or listen to you, as they wouldn't make a good target group otherwise.
Then, if they succeed, at some point it gets bad enough that the media notices, after which the nazis go "look at the silly liberals, thinking everyone is racist these days" and get a lot more open, thereby pushing out the last few people who were initially oblivious to there fascism, or forcing them to endure fascist rethoric to enjoy their hobby's community.
Memes. They hijack pop culture and turn it into a dogwhistle, like if you've seen people randomly saying "is that a jojos reference?" underneath some worryingly bigoted comment on youtube, they're trying to indicate that they're a fellow right wing asshole. For a long time "subscribe to pewdiepie" was used. Both references had some nazi connection, like jojos had a nazi character, and pewdiepie flirted with nazi stuff in a deniable way.
The point is that it's silly and innocuous so that if anybody tries to call it out then they can just gaslight them and point out how silly it is, and they're clearly making something out of nothing.
"Gay coated" is just an amazing eggcorn that I have never heard before.
So eggcorns are misheard phrases that are then reinterpreted in a way that still makes sense in context, and that video makes the point that they're not actually wrong, and sometimes they can compete with the original phrase.
The original term is "gay coded", as in the creators have used commonly recognised "code" to signal that the characters are gay.
But I actually love the idea that they're just slathered in the gay, just lubed up head to toe.
I'd say they're different to bone apple tea because that's a nonsense phrase whereas these could conceivably stand in for the original.
Eggcorn in particular has somewhat replaced acorn in a region of the US where those words sound the same, and the reason it's not wrong is because it is a corn - a seed - and it does have an egg shape in it, so "eggcorn" is descriptively accurate.