Shadowbanning is like a dodge—instead of head-butting such an explosive personality, you let them slide by and rant on into the ether. It can be, and is, abused, but it is also extremely effective and time-efficient when dealing with "the weirdos." (Generally they will go away after some time not getting any engagement, positive or negative.) That can make or break a volunteer force, and if it's a paid moderation team the cost reduction is real.