I had exactly the same thoughts as you, it makes no sense to send data for free to Google and Facebook there. In fact 80% of crypto currency (based on the top 50 of coinmarketcap) are using Google Analytics.

I 100% agree with you. What is the point of claiming using Open Source if at the end all data are gathered at Google. I mean a huge part of crypto currencies are saying that they are anonymous but that's

Thanks Dimitrisp for your support to the Piwik community.

thanks for your answer, it makes sense to me that my article is not detailed enough.