Follower count is not a reliable number on nostr, it fluctuate depending on what relays are running or have downtime. Sharing npub in a trusted and using NIP-05 domain verification is way more reliable. (NIP-05 is however in most cases KYCd, so not anonymous.)

What I'm thinking of is similar to private lists on Twitter. Letting people subscribe to content without publicly sharing their connection to it.

As a complement to the legacy follow system. But a privacy focused client might consider using private lists as default. To counter social graph analysis by malicious actors*.

*Say maybe a paranoid government that want to track down the social connections among those who have been talking sh%t about the dear status quo.