You're completely right.
But if you see the patterns, most of the time, the hate for FF comes from the pre-3D FF fans. Heck, there are people in here that go around saying that FF ended with FF6.
Those kind of people won't ever be satysfied, even if S-E did a FF exactly like FF6, because they nothing will ever match up to their ideals.
As for FF popularity, that wouldn't be an issue, if it's own fans were as close together as almost all popular franchises fans are. You don't see Halo, Mario, Zelda, Dragon Quest, Gran Turismo getting so much flak from it's own fans as FF does. Because they can accept and enjoy whatever comes next in their beloved franchises.
In FF case, the contrary happens, each new FF gets hated because it didn't do all the things fans wanted, so it is worthless.
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