There's also the "your niceness feels transactional and directed". Like, yeah you're overly nice to people you're attracted to, but not really to anyone else. You aren't being a broad spectrum emitter of kindness. Being that person who's cool to everyone is often very attractive, but you gotta get the chip off your shoulder and accept that not everyone is going to be attracted to you, and just generally learn the social skills to have everyone feel happy you're there.