The devs just completely folded to some bogus copyright claims against their extentions

Essentially Kakao Entertainment abused DMCA to get all extensions removed despite the Extensions themselves not containing any DMCA material. What allowed this to spiral so out of control (it started out with only Bato.to, Mangadex and Kissmanga being removed) was that the Tachiyomi devs have absolutely 0 spine and 0 will to prevent DMCA abuse. They just folded at the requests immediately without any sort objection or demand to go through GitHub instead (this approach in particular has worked in warding off false DMCA claims because that way the corporations have to somewhat publicly press their illegitimate claim, worked wonders for youtube-dl afaik)