I agree that the long manifesto on how "pi is wong" is overdoing it. After all, pi works for all intents and purposes (with one disagreement, and it's not even about the math).

On the other hand, tau, while only being 2pi, does make a number of equations look nicer (or fit how others look, in the example about quadratics), and makes understanding angles in radians more intuitive.

I can't find a good reason to keep pi around for any more than historical purpose, and I was curious if anyone had some. My main reason for not changing to tau is a mix of habit and to avoid confusion for my math professors :)