Zaps aren't all that different to read receipt likes here, the ideal that zaps are some sort of signal is just a slogan. (I think if nostr was a huge thriving place it may be different. For now it seems like wishfult honking and sloganeering).

It would also be quite difficult to have a ratio system of likes/zaps as a percentage of followers, because there are so many bot follow accounts on nostr. But that would be better imo. Perhaps it can be done with some sort of follower:likes system taking into account nip05 or WoT. Not sure. But a better trending system is needed.

Nostrband's trending accounts is better, and can be good for discovery.

Atm Primal's trending system is just 'here are some big accounts' and the boring posts they get read receipts for