Freedom of Expression would not be exclusive to any particular manner of voting, there is also the freedom of association for us practicing democracy to use when we identify with common interest against this spam account.
Surely there is community consensus about this accounts posts tagging us being undesirable, we are just humoring ourselves here with the downvoting. The real inception of harassment is the spam this author is putting on the blockchain.
Not sharing the reward pool with a spammer, seems reasonable.