There's an interesting dynamic at play when people talk about meeting people through hobbies, and I see it all the time. If a person wants to meet others "organically," one of the first pieces of advice they'll get is to meet people through hobbies and things that they enjoy. However, that advice is only applicable if you have social, group-oriented hobbies. If your hobbies are individual things like knitting, collecting things, cooking, reading, working out, etc., that advice probably won't apply well to you. However, if you say that, the response will then be "well, broaden your horizons and get new hobbies," but at the same time, people will also tell you "don't join new hobbies just to find people to date."
See how conflicting that can be?
If I have hobbies, they're not good enough if I'm not meeting people through them, so I should get new ones.
If I get new ones solely to meet people because I wasn't interested in it on my own, then that's wrong too.
All I'll say is that not everyone wants to be in a run club or join a rock climbing gym, but the more people get told to "get new hobbies" that'll let them meet people, the more people you'll get who are only there to meet people and they don't care about the hobby.
My best advice would be that, if you have a solo hobby, go do it in public. If you like to read, don't stay home and read. Go to a cafe where people are. If you like to knit, go do that at a park where people are. If you like to work out, consider deliberately going during peak times when other people are there. If your hobby only requires you, just change your environment. You might not need to change hobbies altogether.
ETA: This is not a statement about my own hobbies, I'm just making an observation.