> inform the client of the majority of trusted pubkeys agree with the report or not
The problem with any kind of labeling from ordinary clients perspective (like YakiHonne) is scaling: it takes time to receive the reports, even more time in total will take to receive the reactions to the reports (or their NIP-45 COUNTs ideally). All this just to decide whether to show a post or not.
Yet I think what you suggest is possible and could be useful at least for trust ranking analysis bots.
Or if you mean to request *something like* a NIP-45 COUNT, so relays could aggregate all reaction counts to all spam reports for given posts in a *single* request—this makes a lot of sense for ordinary clients too, yes. Yet this is hard to promote such a feature because some believe this implies not-dumb-enough-relays.