The reason is that they are really dedicated to privacy and protecting your rights. As an additional act of good faith, their newsletters do not include any trackers. They are serious when they say they are privacy focused. And their solutions are compliant with GDPR, without having arguments and weighing words and their meanings against each other.
@Kheo, your question was quite a while ago, but since I did not see anyone else answer it:
Removing GA (Google Analytics) should not affect your visibility in Google Search. Lots of the biggest, most successful sites on the Internet use Adobe Analytics and do quite well. One thing to be aware of if you do switch is that you may be relying on GA to do Google Search Console verification, so you might need to select another way to get access to that data.