When you’re talking with someone in person, it’s probably because of some relationship you have to them (neighbors, friends, school or work relationships).
Online interactions are much more self-selecting, meaning I’d expect people in those conversations to be more passionate about the topic(s).
If someone is disinterested in a topic in real life, you get an obvious signal of their disinterest. If someone is disinterested online, they dematerialize and are replaced by an online NPC who is, on average, quite a bit more interested than the typical person.