You're supposed to use distilled water which is not conductive. At least that used to be the case last I saw liquid cooling.
In the end it's simply not worth it for me. You still need to radiate the heat out, which usually means a big fan, which most air coolers nowadays have anyways.
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.
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.
I've been building my own PCs for a looong time, and I've been skeptical of using water cooling in any of my machines.
This changed recently for me, when I got my first 4000 series nvidia gpu, that fucker is huge! And it runs hot, spewing all of its heat directly into the middle of the case. I had serious concerns with this gpu + massive cpu air cooler getting in the way of positive airflow through my case.
And this is where water cooling made perfect sense to me: transport the heat away from the cpu, thus clearing a ton of space from the middle of the case, then have a radiator at the top of the case dissipate that cpu heat.
This allows for a ton of air to go through my case, evacuating all of that heat blowing out of the gpu. This also allows for other heat sinks on the mobo and other components to passively cool better
It's simple for me. Points of failures of air cooling: fans. Failure states: fan fails, system heat protection kicks in and shuts down.
Water cooling? Points of failure: fans, pumps, tubbings, fittings. Failure states: fan fails (best case), worst case? Liquid goes over electronics while they are powered.