It's a bit of a mixed bag, and the real thing is that there are other people who want to talk about it here. Trust me, I run a Taylor Swift community here, and it is an uphill battle - but it's worth it because there are people who care and enjoy the community.
If you're up for it, choose one or two communities and then nurture them. When reddit imploded 2 years ago we came over and we had a ton of people open hundreds of communities and then abandon them, people just opened them left and right and then expected a large audience the next day. Instead expect it to follow the 90-9-1 rule. Out of a hundred people, 90 of them will lurk and never participate. 9 will comment, and one will post. You will need to be the one to post for a while - but it will grow over time.
Take care of the communities, let them know you're here to stay, and that it's a place where you can chat about it. We're a lot of nerds here, but nerds can also like football, there's [email protected] that is usually pretty quiet but obviously people subscribed to it.
And if you're a swiftie make sure to stop by [email protected]