So it can be said that the temperature "did a 180" when it goes from one to the other.
Hadn’t heard that one before!
Technically, it’s water that freezes at 32F. “Freezing” in F is still 0 just like in C.
It just that 0F is the temperature at which brine freezes. The problem there is that an exact composition of brine was never defined. So for the metric world, they chose straight water.