All from the page's comments:
This is idiotic. He uses an expert tool (from a third party!) that he doen’t know how to use, and when he makes an error, he complains that it’s the fault of the platform and the default interface, and that this is a trap for the unwary novice.
The argument is nonsense. A novice user would not use Cocktail in the first place, nor would a novice even think of un-hiding and trashing hidden system folders.
The default interface is fine. Why do you think the /usr directory is hidden in the first place? Precisely so that novice users don’t delete it by accident.
When you use a tool like Cocktail, you’re voluntarily throwing off the restrictions of the factory-standard UI in order to do what you will and run your own risks. If you don’t have the knowledge to use the tool safely, you have no one but yourself to blame.
He is blaming the Mac OS for a bug in NO-IP.com’s application and his own ignorance using Cocktail.
That’s like saying "Hey, I typed rm -rf in the terminal and now my Mac won’t boot. Mac OS X sucks."