Why aren't turns used more often in math? It seems much more fundamental of a unit compared to degrees and radians. The value of a turn is definite, and other units can be derived from it. The problem with radians is we'll never know exactly what a radian is, unless you're putting it in terms of pi or tau. And degrees are quite arbitrary (360? Where did we get that from?) Turns could be put in terms of transcendental numbers, using fractions. This doesn't need to be done as often, but it's not too inconvenient to do.
360 degrees = 1 turn
2π radians or 𝝉 radians = 1 turn
1/400 gradians = 1 turn
I just think it's more fundamental. The Planck unit of arc, if you will. Probably just my opinion.
My question is simply why radians are used far more than turns as a unit.