I bought FFXI thinking it would be an amazing game. However, I thought:
* It's far too long-winded to get into, and moving on in the game takes too long as well.
* Seeking a party is nigh on impossible.
* Finding a lost party member isn't at all practical.
* You have to start all over again if you start a new job.
* You have to spend hours levelling up before you can do anything significant.
If an online game of FFVII turned out like that, I think Square's reputation would plummet. Their financial turnover was bad enough after FFX, FFX-2 and to top it off, FFXI. XI wasn't ever all that popular. I may still go back to it one day when I have a ridiculous amount of time and money on my hands.
FFXI assumes that everyone playing will be experienced MMORPG players. I've played a lot of Guild Wars, and though it can play a lot like a single player game, its system is a lot easier to use. If a FFVII online game ever came about, I would have no end of complaints if its system was identical to FFXI's.