It's optics, nothing really more than that. Of course, a large amount of people do in fact have FOMO, and won't be able to wait the three months. And, in terms of optics, it's at least a better look than some of the ridiculous BS Microsoft does with even game announcements.
But just contrast this: Microsoft can get Sega & Atlus to outright ignore mentioning the PS version of P3 Reloaded remake everywhere outside of Japan, but Sony can't negotiate for an exclusivity window beyond 3 months for a remake to a game synonymous with PlayStation's image? It's both sad and funny in a sense.
Of course the usual dolts will come out and say the typical braindead talking points about pro-consumerism and "access to games for more people"...all talking points they got fed by Microsoft, BTW. But I digress. They'll come around and say this, meanwhile any company that seems to be struggling these are the same fools who immediate throw Microsoft's name out there to acquire them. Or, they were (and still are) a fierce cheerleader for MS buying ABK, Zenimax and who knows what else in the future. Or they ignore that MS's means of making those games "available to more people" very conveniently still keeps the access to platforms Microsoft has ownership over, be it Xbox consoles, or PCs running Windows, or services using Azure (which includes Game Pass), or lending out rights of the content they would otherwise own and collect money from (such as with the Ubisoft cloud agreement).
"Pro-consumer" is okay as long as Microsoft is still in control of that content one way or another. Anyway, have fun anyone picking Rebirth up Day 1. I'll wait until these games eventually come to PC. No FOMO on my end and there are quite a lot of other games I have to catch up on anyway. I'd just hate to be a paypig being asked to pay the most to help fund cheaper & more feature-rich access to people on other platforms merely a few months later. For the "privilege" of getting it 90 days early, for myself it's just not worth it.
At this point tho that poster is probably not entirely wrong. I'd even say FF Remake Game Pass announcement for Xbox at the TGAs next week is slightly above 50%.
It's pretty clear the honeymoon between Sony and Square-Enix is over. Although I doubt Rebirth will be in Game Pass anytime before December next year. Though, if it DOES go to Game Pass in May, then that's just a harder slap to the face of PS5 owners IMHO.