It definitely seems so to me. We have an odd behavior by a mod that contradicts the norms of this board. Normally a mod only moderates another forum based on clear rules, and only if the other mod is not around to deal with it. But, as you admit, there is no clear rule about closing the threads for suspended posters. So we have a mod who made an unusual decision on his own about a forum he doesn’t moderate.
That seems worthy of note. It seems worthy of hashing out why that decision was made and discussing whether it is something we want to change moving forward. Do we want to have mods jumping into other forums and making debatable decisions? Do we want the new norm to be to close threads when someone is suspended?
Personally, the latter is something I could go either way on. But the former seems something that shouldn’t be. And it would have the added benefit that @What_Exit would not then be the one who has to take the criticism that he stated he doesn’t like.
I would suggest that, in non-emergency situations, you let the mod of the forum make the decision. Or, if they are not present, that you consult with the other mods, not make the decision on you own. That would reduce the burden.
I say let @Miller make the decisions for the Pit, or put @What_Exit on as a pit mod, too.