While ProtonMail’s marketing has always stood out as over the top self-congratulatory, the reaction of people saying “oh no, I need to find an alternative now” represents a fairly naive understanding of the very nature of communication platforms on the internet, especially email.

There is no alternative here. There is no company that will ever solve the problem, within the existing email protocol, where one unencrypted sender (say, marketing emails) can send to a so-called “encrypted receiver” and not have an intermediary able to temporarily read the emails. This is inherent in the design of the system. ProtonMail is not end-to-end encrypted in this case, and no email provider can be on the traditional web.

There are no alternatives. There is no hard, scientific, mathematical solution to this. The best you’ll get is “soft encryption”—the equivalent of encryption where the third party offering the service chooses the encryption key.