One of the biggest reasons why we have scientific magic in RPGs is that it gives agency to the player. When magic is a relatively mundane tool, it becomes an op

One of the biggest reasons why we have scientific magic in RPGs is that it gives agency to the player. When magic is a relatively mundane tool, it becomes an option that a player can rely on, and that is really important. If magic is unknowable, then it forces the GM to use the magic rather than the players. This takes agency away from the players and makes it more of a movie (zero-player game) than a game. Personally, I find the "scientific for mundane things, but mythical for greater things" model to be the most desirable, because it's directly applicable to how we view magic in the real world - any sufficiently advanced technology is viewed as magic. If you show an 18th-century machinist a laser-etched piece, he'll be mystified. And as you gain wisdom, knowledge, and experience, the current mystery slowly unravels, to reveal still more mysteries beyond. So, the mechanism to cast a small fireball should be mundane and understandable. In contrast, the fact that 500 years ago, a great sage burned an entire forest to ash should be mystical and unknowable... for now. Maybe it will always be a mystery. Maybe the method will become known but shown to be impossible with current abilities. Maybe the magician of the group will attain that power, but at some great cost. It's up to the GM. This way, we get the best of both worlds - the delight and intrigue of mysterious things, and the agency of being able to manipulate known rules to solve problems.