What? No its not. Estelle has Rita mess with her formula to copy Ravens blastia so she can use her magic with her life force instead of massive quantities of aer. Before the final dungeon, Ravens still using his life force. I know this because a sidequest has Yuri explicitly telling Raven that he can get Rita to do him a solid and fix him, and hes all like Uh... I dont want that brat to know I owe her for my life, before he collapses from fatigue.
The only ones who have Spirit Magic by the end of the game are Estelle (obviously) and Rita.