London also makes it easy to take up hobbies, and I imagine that would be more consistent in big cities.

I'm in NYC, and hobbies here are INSANELY expensive. Sure, there multiple makerspaces, but their memberships are all $400/mo+. Classes are expensive. Rent is so high that no one has room for hobby equipment. I would like to try brewing, but have nowhere to put a big jug. There are a lot of hobbies I would like to try but I have to space for it. Also, there's not a lot of free and open space for hobbyist groups.

Contrarily, I've also lived in the Midwest and the Pacific Northwest in mid-sized cities, and THERE was the sweet spot for hobbies. Big enough that there are people interested in esoteric things, but small enough that it was affordable and there was space for it.

Also, I actually prefer the more tight-knit groups that result from esoteric hobbies in midsized cities. In NYC, there are hundreds of people interested in Underwater Basketweaving, but in Generic Midwest City there are only 10, and so those 10 people become a close-knit community.

Furthermore, in NYC it takes an hour to get ANYWHERE. For one of my main "LOCAL" hobby groups, all the get-togethers are anywhere from 1:30-2:00 away. Almost everyone I've dated here lives about an hour away (the exception is if they happen to live off the same subway line). But in Generic Midwest Town, you're never more than half an hour away from local groups. Travelling two hours would put you in a completely different city/scene.