You don't, but it's considerably quieter to use a liquid cooler on current high-end CPUs because of the amount of heat they dissipate. My current CPU has a considerably higher TDP than my last desktop's. I finally broke down and put an AIO cooler on the new one, and all the fans on the radiator can run at a much lower speed than my last CPU because the radiator is a lot larger than one hanging directly off the CPU, can dump heat to the air a lot more readily.

The GPU on that system, which doesn't use liquid cooling, has to have multiple slots and a supporting rail to support the weight because it has a huge heatsink hanging on a PCI slot that was never intended to support that kind of load, and the fans are far more spun up when it heats up.

The amount of power involved these days is getting pretty high. My early PCs could manage with entirely passive cooling, just a heatsink. Today, the above CPU dumps 250W and the above GPU 400W. I have a small space heater in the same room that, on low, runs at 400W.

Frankly, if I had a convenient mounting point in the case for the radiator, with the benefit of hindsight, I'd seriously have considered sticking an AIO liquid-cooled GPU in there

there are a few manufacturers that do those. The GPU is a lot louder than the CPU when both are spun up.

I will kind of agree on the RGB LEDs, though. It's getting obnoxiously difficult to find desktop hardware that doesn't have those. My last build, I was having difficulty finding DIMMs that didn't have RGB LEDs; not normally a component that I think of anyone wanting to make visible.

I'm kind of wondering whether we'll get to the point where one just has a standard attachment point for liquid and just hooks the hardware's attachment into a larger system that circulates fluid. Datacenters would become quiet places.