I also had my proposals to block them (as spam), but some said that Bitcoin network should not start censoring arbitrarily (which is also something I agree with). I have a feeling the truth is somewhere in between.
I wouldn't call it "arbitrary" if it's one person spamming the blockchain for so long. The reason I still think it's one person is because of the massive numbers of similar transactions that keep flooding the blockchain. If fees aren't enough to deter spammers, I'd like to bring back the "coin days destroyed" priority mechanism. But it's going to be difficult to get miners on board.