Hard to find out which witness that is, I looked through a few accounts but couldn't find a very familiar name :D
This pie chart and the ones of the voted accounts definitely point to a circle that could use some "love". Interestingly slowwalker is in there too.
Bots with daily stats aren't per se useless (see the curangel one :P), but sure, some of them would be valid targets for sure.
In the end it's up to the curangel delegators to decide what to downvote. I keep out myself of that decision, because the weight is spread by stake and my delegation is so big that it wouldn't leave much for the power for the rest of the suggestions.
It's on the CN side. Mostly the Adm users.