It might make the thread irrelevant, but the problem is fixed at too high a price.
Consider right now you have at least a couple of choices as Aether and Crystal have vastly different atmospheres in particular. With this proposal, there would be just one North American player pool, and I've seen how this plays out in practice: when communities are merged, the "hardcore tryhard" crowd INVARIABLY bullies out the more laid back community to the point that the latter no longer exists, and everyone feels forced to adopt that "keep up with the Joneses" mentality just to play the game with all the conflict aggravation that entails.
Look how WoW has evolved since it went from separate server communities to choose from to a regionwide group finder: you might get a group faster (well, IF you have enough of that hardcore push mindset in you, otherwise you just get gatekept and fed homilies about "not being entitled to a group" like, we got groups just fine before we were thrown into the same pool against our will, unless you were on the deadest of dead realms ...), but the atmosphere has been unified to basically that one single acceptable mindset for an entire continent.
Or the hunt community, where every world used to have its own, now there is a single acceptable culture per entire datacenter (typically built around getting the serious players their Nuts and Tomestones as efficiently as possible) leaving the kind of people that chose most Worlds out of luck, to say nothing of the old days (as recent as early 4.x really) where FCs would see an A rank and get together to pick it off.
This is probably an advantage though. FATEs are easy enough that you don't need more than one or two people for most, and if anything tend to work better that way (especially now that getting Gold credit is much more important than ever, especially for catch up players, who need 66 Golds per zone to even unlock all the gemstone items).
I'm on Maduin, which is usually seen as perhaps the least active world? And I still often find myself at least world traveling when I need bicolor gems because finding uncontested (because if it's already going, there's a good chance you aren't getting Gold by the time you make it, if you even do) FATEs on this server is surprisingly difficult.
This seems to be a chronic problem with XIV: there's not really much wiggle room to give out meaningful carrots, since EXP grows on trees (except maybe at the ten-level breakpoints, anyways), Gil is so downplayed compared to most games (and given how much trouble we have with RMT here even with that fact, probably should stay that way), and it's already super easy to cap your weekly Tomestones, while there's barely any wiggle room in the ilvl schedule to add extra gear incentives without problem.
About all that's left is bonus uncapped Tomestones, but those are pretty easy to farm anyways.
Which leaves sticks, and nobody likes sticks.