Flagging the bid-bot posts should work just as well.

If whales are soley motivated by money, and the bid-bot posts they've lent their steempower to, stop earning as well, they'll find another way to use their steempower (perhaps curatgion guilds).

It feels like operation-cleanup is aimed at writers on the front page, but it is really aimed at the delegators who support the bid-bots with their steempower.