Yeah there have been some threads about it before in a few places, such as in some chatrooms. I don't think it's worth paying too much attention to. Fairly likely it is just some arbitrary individual either running one of the few strong Chinese bots or other privately-developed bots, or running a modified version of KataGo itself, on sufficient hardware to compensate the disadvantage of that opening. (And yes, the fact that a strong bot plays such an opening does not mean the opening is good - it is almost certainly just hardcoded. Keep in mind that even more a suboptimal opening, superhuman-level bots can give themselves or other bots full handicap stones and win if there is a hardware advantage).
I might guess they are doing it mostly for fun, or possibly to try to troll people who would pay a lot of attention to things like this into believing that the "black hole" opening is some uniquely mysterious powerful opening.
