I’ve discussed it in other channels, but the main problem is that what will most likely happen if an account is blocked this way is it will power down. They will either cash out all of their STEEM, or power up a new account and turn it into a ‘wack-a-mole’ game.

For the most part, the same effect can be accomplished using downvoting, except it is easier to target specific behavior (rather than the whole account) and stop the downvoting if the bad behavior stops.