Observe their interactions with other people and what their motivations seem to be. For instance, I have a friend who likes hanging out with people who are entertaining, but if it’s someone who has something additional to offer him - people who stream and have a larger audience, women, people who might donate to him - he seems particularly excited even when there’s nothing about their personality that would seem to lead to that. So, does he like me for me? Probably because I don’t have a lot to offer him. But does he really like this one streamer with 50x as many subs as he has? Probably just because he wants to use them to boost his own profile.