This is so, SO underwhelming.
Not only will we not be seeing class sets return in 9.1, but the raid armor sets are simply going to be a transmog-able version of the legendary sets that we've seen already.
No new conduits either. No new customizations. No new heritage sets.
Here's the interview on WoWhead: https://www.wowhead.com/news=321033....-mega#comments