Anything that is “degrees” is the devils work. Radians are so neat and IIRC it makes a lot of trigonometry math easier. Yes, they’re a bit weird to get into once one has been indoctrinated to degrees, but (pi/2) radians is just so nice.
The amount of things allowed by ISO 8601 is even more than what’s allowed by RFC 3339, if you take the time to look at ijmacd.github.io/rfc3339-iso8601/