Simply put, not everything that has a "water/liquid" in the name will do wonders for cooling.
If you have 160mm clearance for CPU cooler, a decent air cooler (~50$ and up) will usually perform same or better as most 240 AiOs.
Air coolers will be usually quieter for the same performance.
Liquid cooling practical reasons are space constrains and aesthetics. There is also a case of over 200W CPUs. High end custom loops do few degree better cooling (at lower noise) and allow another 100-200MHz overclock. that comes with the price difference of few hundreds $.
It is (custom loops) nice to have and cool hobby, but otherwise, get decent air cooler.
As for AiOs, except those niche use cases, not worth it.