It's a centralised blocklist that likes to not provide receipts for anything, and that is known for disproportionately targeting transfem-run instances (
https://thebad.space)
The guy behind it wanted $40,000 (or something like that) to build a clone of already-existing fedi software that would sync with the blocklist
I said that that was a waste of money, so I was branded a "racist" and blocked by a bunch of instances
It's a similar pattern to what happened to many other instances that spoke against the idea