Hero installed new janitors that he sourced from his existing companies.  They are specifically curating a few of the boards in order to better data mine.  /d/ had too much heterogeny in its postings and niche fetishes.  So they created /aco/  to hold a lot of the stuff they cannot sell (he runs a few datamining companies in china and and japan).  This includes deleting not just Non-sino/Nippon art, but also the fetishes that are not as popular in those markets.  There was a whole article about it.  I will try to find it, but it actually explains what was GOING to happen in detail, and the last couple weeks have followed pretty closely. 

That is also why the janitor applicants from the last influx did not need to have any legal documentation.  Cause they are being staffed by Hero and they weren't really accepting applications, just one or 2 maybe to throw off the scent.  It is all very tinfoil hat sounding, but in most ways it is similar to the kind of shenanigans at Tektronix and Fluke (the 87 V main board debacle anyone?  A rugged RMS multimeter for mains power that is killed by GSM data noise? really?) once they were bought out by Danaher ( I live and work less than a mile from Tek Maxim Intel Tyco and have worked at some of them.  Very tight knit community, there are no secrets on the HR side, and only secrets on the product side)  4Chan is becoming Facebook on the back end.  And since /co/ and /d/ are not worth much to him on the western side of the pond they are being curated away from the cash, like weeding a garden.  You could remake the same thread in /aco/ but it will get lost in the /co/ /d/ shitposting wars.