It's not just for freezing. Water will eat soft metals. Especially if the engine has a hot spot. And water with WW will change in PH quicker as well.
Water is great at the track where you have constant airflow all the time. But at a traffic light.......
Peak Global is the only coolant I know of that'll protect soft metals, without depositing minerals in coolers and such. It meets Cat, Cummins, DD, Mercruiser, Volvo, MTU, Ford, etc. etc. That's the catch with them. One brand wants a coolant that'll protect soft metals. But those same protective chemicals clog the coolers on the other brands so they recommend something different.
Too bad that Peak Global (pinkish red) is super leaky. Thin synthetic that'll leak any chance it gets. Even from perfectly good seals and gaskets sometimes. And where it leaks from it leaves super hard stalagmites and pink concrete stains. Sometimes it'll even self seal a hole in a hose like a tire sealant (not sure if it's supposed to do that). No free lunch I guess, there's always a catch.