It's definitely a personal preference, but it's a very... strong personal preference and in many cases that's for good reason, in both directions. Water cooling performance is typically incredible and if you are overclocking or otherwise generating a lot of heat in a small space or pursuing very high performance, it not only can manage that effectively but it can do it while being quiet, properly designed it can be pretty close to silent, that's real nice. The downside is that it's expensive and it's... water. It's not necessarily maintenance-free, unless you're using an all-in-one (AIO) but that comes with its own limitations, but the biggest problem in my opinion is that when (not if) it fails, it has a high chance of being a computer-ending event. When an air-cooler fails your PC will start throttling, might shut down, in a rare case something might be damaged from overheating, but 99% of the time you just replace a fan, blow out some fins, and it's happy as can be again after that little hiccup. When a water-cooler fails... it's typically a big mess. Both practically and financially.

With water cooling, I think it's fair to say they are either people who have regretted water cooling a PC at least once, or they are people who haven't regretted water cooling a PC yet. Few people can ever say they've regretted using air-cooling in a PC, and I suspect anyone who would say they regret air-cooling a PC, probably also falls into the category of someone who hasn't regretted water cooling a PC yet.