Nomura had to help other projects multiple times. SE made him postpone his project to help with FFXIII/FFXIII-2/Lightning Returns FFXIII, and to help save FFXIV.
Also let me remind you, FFXIV is a smashing success, and is also SE most profitable game, AND XIV's revenue pays for a lot for XV. So thanks Nomura. Wouldn't even have an FFXV without FFXIV and its devoted community.
Oh get off your high horse. One game doesn't "pay" for another one. They pay for themselves. Only an idiot would make a game knowing they're going to lose money on it but do it anyway just because some other game is making money.
And there absolutely would have been an FFXV without FF Online 2, and it would have come much sooner as well!