Water coolers nowadays are great yes, but remember that not all water cooling is alike. An AIO water cooler (All-In-One) which is the most common on the market, is not necessarily any more effective than air cooling. In fact, the top end air coolers can often perform the same or better as AIO
(Custom loops are a different matter altogether - but most don't need these).
Yes, water coolers tend to look nice, and yes, they are much more useful if you're a little tight on space in the centre of the case, but if you're JUST looking for performance, then an air cooler is perfectly suitable.
You can see a pretty good comparison here:
https://www.tomshardware.com/reviews/best-cpu-coolers,4181-2.html
We're not saying they're all like for like - just you don't have to immediately jump to Water Cooling. As is well put here by another member:
Below 250w, air = aio only in its respective ranges.
Corsair H45/55/60 = CM hyper212 evo. Same capacity, negligible difference in temps. Same for any 120mm aio, you are looking at @ 140w, same as all those budget air coolers. The differences in temps will be due to the efficiency of the cooler and effectiveness of the fan.
It's only when getting to 250w output that even the largest air coolers such as the Cryorig R1, Noctua NH-D15 etc peak out, and you'd need a 280mm/360mm AIO, simply due to capacity. You want to run a i9 9900k flat out, don't bother with air, that cpu hits 250w with all core 5GHz no issue.
Noise: created by fans. Doesn't matter if it's air or aio, crappy fans = loud. No point comparing an old h100i to a NH-D15, the difference in fans speaks volumes.
Leaks: yep. Sure do. 99% caused by installer putting pressure on the fittings. Factory leaks happen as often as heatsinks with warped bases or leaking heatpipes. All about quality control.