It’s definitely real, at least for the amateur astronomy subs I (used to) mod. I suspect a lot of the traffic to askastrophotography or telescopes is from people googling stuff and browsing though mobile web, but since /r/astrophotography is just photos, most are just on the app
Iirc the original goal was ‘at least 10’ but maybe up to 100 flights for a booster. No way to really know without flying them a lot