As noted in a number of threads H2O cooling is more a hobby than a set-and-forget type of PC CPU cooling system.
I've pretty much set-and-forgotten my watercooling loop. Yes, it requires more 'initial' setup and once a year maintenance, but other than that- a well built loop shouldn't have any issues. Yes, it is just as much hobby as it is cooling solution- which is the fantastic beauty of it all. Just because you express a fear of water next to electronics, doesn't mean you should attempt to sway people's opinions of avoiding it because 'it causes damage to components'.
I haven't touched the water, fitting or block in over a year. Same water has been in there about 2.5 years or so, with no issues.
In addition leaks on these closed loop systems have been know to damaged other PC components which doesn't happen with an air-cooled HSF.
The vast, vast majority of LCS coolers don't leak- the ones that do are pretty much 2-3 years outdated anyway (Corsair H50).
To counter this, there are many people who have incorrectly installed air coolers and caused motherboard damage or heatsink damage due to breaking PCB or breaking/bending heatpipes. Also, I've heard of many people breaking off capacitors and components because they are trying to mount a cooler too tight, or apply too much force during install and causing motherboard damage.
I believe the real issue lies with people not reading directions, gaining knowledge, cutting corners or simply being careless- not that a specific cooling option is to blame for damage. While I completely agree with the majority of your statements, let's not be wrongly biased in the air-vs-watercooling preference.