The website linked above is filled with false information. We have in fact attempted to reach the author and clarify this, but haven't heard back. Some of the points have been clarified here: https://web.archive.org/web/20210727224547/https://serpentsec.1337.cx/i-was-asked-to-review-an-article-from , as well as in direct communication with our users: https://www.reddit.com/r/ProtonMail/comments/d58cq1/protonmail_questions_and_concerns/
Regarding the recent revelations about surveillance, Proton users are not impacted, because we aren't considered a telecommunications service: https://proton.me/blog/court-strengthens-email-privacy (1/2)
@SoulKeeper While we rely on Google Play Store services for push notifications, they are end-to-end encrypted. To stay private when using Proton Mail on an Android phone, we recommend trying some of these tips: https://proton.me/blog/android-privacy .
We are also working on a complete rewrite of our Android app, which will allow for the improved functionalities and features to be added.
@birdcat Please read the edited version of our response above, and accept our sincere apologies for sharing some links that were irrelevant to your original concerns: https://mastodon.social/@protonmail/111958985077770856.
The benefits of running Proton's services under Swiss legislation described in the article above remain correct.