There's a lot of money to be made in sunset industries, where you acquire cheap and keep it barely running for those still paying.

Fixing meetup, or making something that works is a fun mental-challenge.

Something like geo-specific chatrooms that unlock IRL functionality once you get enough members, and remove it if nobody shows up might be worth a try.

Or maybe most people in the US live in low-density suburbs and won't go to anything because parking/driving is a hassle, idk.