I think water is rather rare as a coolant these days. Organics (chemical sense not farming sense) like propylene glycol or some kind of glyme aren't potentially corrosive to metals if spilled, are harder to grow shit in, have lower volatility, and have a higher thermal limit. Maybe also with a little bit of antifouling agent thrown in. My main gripe with them is that if you do spill them, they don't evaporate and you're slipping over the floor for the next few days because you missed a spot.

But yeah, air cooling ftw

Liquid coolers are by definition just an extra heat exchange step unless you're venting heat into the ocean or something like a nuclear plant. Otherwise, the atmosphere is your final heat sink either way.

Unless a liquid cooling radiator is significantly larger than the air cooler that would fit directly on the CPU there's no point whatsoever.

No coolant is non-conductive after it leaks. It will mix with dust that has built up on the surfaces of the components and become conductive.

The main reason for distilled water is to prevent corrosion and deposits forming inside the loop.