"You should not track your users. If you need anonymous data, you should ask your users first."
Now I'm imagining a website where when when you first visit it, you get a popup like "for capacity planning purposes, this website would like to record that you visited [yes] [no]". I wonder if this author would like such a website?
The article was targeting another scenario: An installed app that tracks users.
Obviously, for websites this would rather translate to: Do not track your users, especially not using 3rd party services.
I hope you realize, that "opt-out" doesn't work without tracking the user either. Which kinda reduces the point of not wanting to be tracked to absurdity.
It seems reasonable to want some analytics and it looks like they did a good job from a privacy standpoint (random IDs that you can even change if you wish). They even allow you to opt-out. There is simply no betrayal here.
Why is that a problem? If you are the type of person that is paranoid about anonymous usage data you will be very well versed in opting out of things because that's pretty much the standard. Homebrew is even notifying users that they are starting analytics and that you can opt-out. Here's what I just got on my terminal:
==> Homebrew has enabled anonymous aggregate user behaviour analytics
Read the analytics documentation (and how to opt-out) here:
https://git.io/brew-analytics
The vast majority of users want Homebrew to work better and are fine with the developers knowing which packages are the most popular. This is not "betrayal".
Have you ever looked at Google Analytics information? They don't even give you individual IP addresses or anything like that. They actually do a GOOD job of anonymyzing data like that. You could track more information if you did it by yourself without Google Analytics. It's not really a big deal for someone to track what languages and what browsers people use on their sites.
The problem is not what the site owner is able to see, but what Google sees. And it collects information about every site you visit, every article you read. It has access to all other information, like your browser fingerprint, etc. It does this even without being a Google customer - If you are, it get's worse - It can correlate it with every mail you get, every term you search, every step you take. This is a fundamental problem, and the magnitude is incredibly scary.