I think the region is locked in FFXIV because game keys are locked to that region. If you could just rebuy the game and expansion for your new region it would be annoying but preferable to simply being forever locked out by no longer being able to match your account region if you move from say, the USA to England.

And even below that, people are getting screwed if they move within their own region. Changed country within EU? Sucks to be you, start a new account because you can’t update country of address.