Is the MMO and single player FF fanbase divided?

[Yasuhiro]

I don't mind the spell names either way, I, II, III is simple to follow but I'm familiar with progressive skill names being different, too (agi, agilao, agidyne).

Is that Shin Megami Tensei? and for me II, III just means a better version of that spell like it was in Final Fantasy II and XI
Ara and Aga spells (Spell II and Spell III) tend to be different like Ara and Aga spellsin FF usually are AoE or in RPG terms multi target spells. That's why the naming bothers me just seems like a disservice to Final Fantasy fans and pandering to those that have no clue.

Prior to this, the only FF game I played was X-2 that someone left in my ps2. .

That's probably like the worst game to get an impression on the series glad it didn't sour your opinion on it.