I initially added it on the blocked instances, but then reverted it after a day because it looked like there is 1 user who subscribed to a lemmygrad.ml community, & nothing had come from it yet (bad or good) so I thought taking a unilateral decision something that shouldn't be done and having a civil discussion around the cost benefit of having them allowed/blocked.
This 1 subscriber triggered the federation.
And this (possibly same user) is the reason why you saw all the "backlog" of posts in All.
While I am not against adding it back to blocked instances if it ends up causing an issue, blocking it without a discussion would be against the openness I want to foster in this community. The only reason I would block an instance would be due to an attack against Reddthat, or the majority of users from that instance cause a problem with us.
Thus here we are, having a discussion about it. (Pinned to Local for everyone to see and discuss)