Honestly, I really don't understand why. I can't find a sound technical reason why not. As this product is "approved for racing on paved surfaces". It utilizes a "glycol blend", just like the other manufactures use. None use pure ethylene-glycol, or they would have the antifreeze capability. It boils down to is it slippery/pain to clean or not, and it's not anymore slippery or painful to clean than the competitors. Lots of racing orgs authorize it. I'm not going to fight City Hall though either.
The problem I have, is accordingly to my dealer my warranty is null and void for any cooling system component if I use Water Wetter (supposedly worst corrosion protection and lubrication available), but Maxima Cool Aide is covered by my dealer. Royal Purple Ice and Motul Mo cool are allowable too. Motul seems to be on par with Water Wetter, from a corrosion inhibitor standpoint. Royal Purple looks promising though. I am going to see if my dealer will warranty it. It appears to advertise similar corrosion inhibitor and lubrication performance to Cool Aide.