This is actually very tricky, here is brief breakdown:
Noctua NH-D15, and even UH-14S,
destroy 90perc. of AIO loops. That's because slim radiator of poor design, terribly weak Asetec pump, narrow tubing,etc...
NH-D15 can currently dissipate roughly 320W of heat, at full RPM (1500), UH-14S 250W. This is for regular platforms like AMD AM4 and Intel LGA1151.
For big platform like AMD TR4, only few of the above coolers are available because you need full heatspreader coverage, so those tests also often include adapted coolers and those of course, perform terrible.
But even for TR4, only two stand-out coolers are available, UH-14S TR4 (D15 will be available in Q1/2020...sadly) and Enermax Liqtech II. The former still dissipates only 250W, so good enough for not overclocking the chip.
Enermax claims it can dissipate up to 500W.
Both of these are theoretical bullshit numbers. With good case ambient and airflow, Noctua UH-14S TR4 could dissipate in peaks up to 300W at 1500RPM. Enermax on other hand, is using 2300RPM, which will sound like tornado when placed next to radiotor (most of noise is not from fans, but air turbulence through pressure).
If you would equilize these coolers for accoustic performance, i.e how much do they perform at 30dB, it would be like 1500RPM for Noctua and 1200 RPM for Enermax (rough approximations, depends on position, case,etc..) but Enermax would ultimately still win, giving you maybe 8-10C better Delta (temperature difference over ambient).
So AIO is the winner this time, but it's only this particular AIO (Enermax), no other, and only on this specific platform, TR4. There are no universal rules.
Next year, the clear winner will be new NH-D15 TR4, and it will come in full black :- ) heatsink+fans.