That's true - it does serve all events But since it only allows writing events from keys you've white-listed, events that tag the whitelisted keys, and kind 10002 events, there's not much else for it to serve. Is the concern that it serves events from others that tag you?
Maybe we can get Doug Hoyte (npub1yxp…qud4) to add read policy plugins to strfry to mirror the write policy plugins though I could imagine that having some performance implications.