Keep in mind, Yoshi-P said if FFXIV ever did go F2P, then the game would probably remain P2P but maybe just have some F2P servers. It's pretty clear that P2P is the way to go, otherwise, more developers would just launch their games as F2P.
If you simply think logically this is what you will come up with.
Free to play makes more money, however free to play means you have to give the game away as a free download.
If you launch as pay to play, you can sell boxes for $30-60. Wait 12 months, go free to play (this is what I can see XIV doing just as those others are going to do).
You just got the best of both worlds. Publishers aren't launching as p2p because it's the better option, they are doing it because they can sell you the game that way and get a lump of money upfront.