I don't know how this community will hold between 7.5 and 8.0, especially given it'll be approximately another 10 month gap in content. This is on-top of the content droughts from the delayed patch cycle. Sure, we might have Occult Crescent 2.0 and the Deep Dungeon to keep us occupied, but... that's not going to hold us for 10+ months.
There's already the possibility of the next Ultimate being on the chopping block by Yoshida's disastrous language in that Monster Hunter article. Even if that Ultimate comes out, that's only going to keep raiders' attentions for... what? A month to three months at max? Once people clear that, they're all going to fuck off and unsubscribe.
So, unless they have something else up their sleeve to keep us entertained, I don't see how Square Enix is expecting us to stay subscribed for 1.5 years.