Back in the beginning days of Steem it was like that a lot.

Now that it's 50/50 rewards people just follow an active curation trail, don't post or comment ever, and earn money for doing nothing. Proof Of Brain has less incentive to function. It might cut down on spammers and self upvotes, but now you gotta downvote other people's posts in order to downvote people who are milking rewards pool by buying HP and following curation trails.