True, antifreeze contains small amounts of corrosion inhibitor but also loads of horrible messy glycol. The inhibitors are generally borates and silicates.

The cooling properties of water ethylene glycol (WEG) are actually slightly worse than neat water - it's primarily about preventing freezing damage. Best freezing protection is around the 2:1 ratio (glycol:water) which protects down to around -40C. Neat glycol itself actually freezes at only -13C. I can't work in a freezing workshop and have heating to protect my machines.

If you want to prevent corrosion and biological growth, you could add a tiny squirt of an inhibitor such as Fernox F1 to the fill (£9 from Toolstation etc). One bottle would last you many years and protect many machines.
https://fernox.com/product/protector-f1-500ml/