When I see that image I'm impressed to see 1.1 milloin followers.  Not because it's a lot of users (which it is), but because I wonder how nostr would do a query with so many authors in it.  They definitely have some good bits. 

 That number would need to be cached somewhere to work on Nostr. As new follows/unfollows get tallied, and occasionally doing an audit of follow lists within a set of relays.