I could be wrong but you need a central source to determine popular topics. And I think this is hard to do with relays. But maybe devs know better.

We had this onboarding designed months ago on Snort but it was difficult to implement if I’m not mistaken. Will tag nostr:npub1v0lxxxxutpvrelsksy8cdhgfux9l6a42hsj2qzquu2zk7vc9qnkszrqj49 if he wants to chime in.