Focusing more heavily on magic vs melee for the Red Mage fits the Final Fantasy XIV lore. After all, the Red Mages are former Black and White Mages that worked together to create an entirely new school of magic. They just added swordplay into it as a way to augment their skill set a bit further. This isn't the classic Red Mage. It's right on the Stormblood page.

"The survivors gathered from near and far, and amongst them were refugees of the sorcerous cities of Mhach and Amdapor.

These sworn enemies buried their history for the sake of the future, and cast aside their vestments of black and white. Upon the remnants of their arts a new discipline was built, and the first red mages stepped forward with rapiers in hand to fight back against the rising tides of destruction."