I find there's a balance to it. Certain spells are used within the lore, as others have said. Or the NPCs in game directly refer to spells, like Holy. Other things like Fire 2, Ruin 3, etc, I don't think are necessarily said in game, but there's probably a general "fire" spell or so. It certainly doesn't help that a lot of magic was moved and redefined in a Battle Team vs Lore Team shift from 1.0 before and after Yoshi-P, which was then carried over into 2.0 and later.
Because jobs weren't actually in the game until patch 1.20, they were effectively only there as NPC skills and were for the most part, their own things. Then classes were reworked to what we have today. So "Flare" might be a named spell, but perhaps "Blizzard" is not.
In my own RP, I dabble with arcanima. I usually make reference to geometries for tasks, but I don't typically name anything directly. Each school of magic/techniques likely has far more practices than what we see in game. Battle mechanics are lore-inspired, but I don't think they're necessarily bidirectional.
Because jobs weren't actually in the game until patch 1.20, they were effectively only there as NPC skills and were for the most part, their own things. Then classes were reworked to what we have today. So "Flare" might be a named spell, but perhaps "Blizzard" is not.
In my own RP, I dabble with arcanima. I usually make reference to geometries for tasks, but I don't typically name anything directly. Each school of magic/techniques likely has far more practices than what we see in game. Battle mechanics are lore-inspired, but I don't think they're necessarily bidirectional.