My two cents: I agree that I wish Occult would be a 91-100 with a sync up to 100 even though I won't need it.
By the time it comes out, I won't need it to level anything, but I'd still like it since I recognize that if people are using the place to level their classes then it means more people will be participating now and down the line. Bozja is still very active to this day because a lot of people use it to level and it makes for a fun community. If it weren't for people leveling, I don't think it would be nearly as active as it is now, so that aspect really helps people who are late to the game but want old relics as well as people who just enjoy the content to have more people to do things with. Honestly Bozja is one of the few places where I've actually felt like the game has a community doing content at. I did 16 of the classes from 71-90 in there due to it feeling more community based. I know Eureka is still active because it is good for gil, so let us hope that Occult is too so people have reason to do it still several patches later or even next expac.
For those saying Deep Dungeon is the leveling thing. It is, but why can't both be to offer people different options?
I personally like the community aspect, seeing familiar faces, and chatting people up in Bozja while waiting for events to start more than I enjoy spamming the same floors of a DD with people I'll likely never see again in my lifetime. And offering both is a nice way for people to get to pick what they want to do and help them not get bored since they could bounce between.
Ultimately, I think it would have been nice, but it is definitely too late for a change like that (or it would be a miracle if they changed it).