For filter.nostr.wine (and the various services powered by the aggregator) we just use some rules based and repetitive spam filters. We haven’t published them just because they are trivial to evade. The normal nostr.wine doesn’t have any filtering besides being a paid relay.

When I get some time I plan to work on our version of npub trust rank and then we will transition the aggregator to use that. Has to be well thought out to not be trivially gameable though so may take some time.