Other ideas just off-hand would be: - road biking : Most cities have groups who ride regularly. Always a better idea to join a group, both for motivation and visibility. - cooking : This can be solitary or social (if you invite people for a meal). It’s easy to learn and hard to master, and the worst case is you end up with food. - art / music : Take an art class. Local community colleges tend to have art 101 or other similar intro classes available for pretty cheap. Being creative is a great way to exercise parts of our brains that most of us don’t use much. - reading : Join a book club. Stick with fantasy or sci-fi or something else which can’t accidentally become work. Go to a coffee shop and spend a few hours being antisocial but still in the vicinity of others. - video games : Not much to say here. Video games are just fun and depending on the game, a great way to make friends is to join a guild in some competitive team game. I personally love a good rogue-like platformer (a.k.a Hollow Knight, when is the sequel supposed to release again?). - D&D (or other table top games) : Same idea as video games but without the tech and with the guild built in. Check out a local game store and ask about joining a one-off.
Anyway, even if none of these work for you, I hope it at least helps get you thinking.