Google analytics opt-out extension?

While clicking around a website's privacy policy, I found an option "if you don't want us or Google to use analytics, click here" more or less.

It's Google own opt out extension, https://tools.google.com/dlpage/gaoptout

Is it that simple to block sites use of Google analytics? I mean, otherwise, are Privacy Badger or Port Authority doing the same thing, just not Google's tool? Is Google's a honeypot or Trojan horse you think?