FFXI still going after 11 years with subscription model, yo. Beside, it came out during a different time, the mmorpg audience wasn't so large and it didn't become popular worldwide until much later when it was ported to PC and Xbox.
First reality check.
Lineage II reached 2 million active accounts, Lineage was even higher beating 3 and those were subscription asian MMO that happen to predate WoW (Lineage II by months, both 2004 games), FF XI? try 2002 in Japan and
2004 in the rest of the world (2003 in NA on PC), in 2002 Lineage had reached 3 million active accounts, so "wasn't so large" is complete bullshit, perhaps not in the west it was so large as Everquest risen to 400k after a couple of years and peaked at the same numbers as FF XI at the exact same time.
FF XI peaked at 550k active accounts, not saying its not successful but AoC reached 700k, Warhammer 800k so when I said that I meant that Final Fantasy XI
by name alone didnt sold as their mainline games did, the whole fucking point is if you are cashing on reaching 1m subscribers because of brand recognition you are in for a rude awakening.
Oh the big boys are by order of reaching 1M ... Lineage, Lineage II, WoW, RuneScape, Aion and TOR.
Second, the point was name recognition is not going to make it sell ... being Final Fantasy did not even make FF XI be more popular that Lineage, it was completely left in the dust by WoW (that left everything else in the dust as well) and never risen up after it peaked in middle of 2004.
In fact since I hate having to slap facts around ... FF XI Xbox port was in 2006, the "PC port" was in 2002 in Japan and 2003 in NA ... in 2006 FF XI had 500k active accounts that was the number that maintained since 2005 to 2009, mean not only it was not "much later" because it was less that 2 years apart on PC (especially in NA were the PC "port" come before the PS2 version) and there where no actual changes when the Xbox version come out.