Let's not forget protonmail.com was previously protonmail.ch. Moving domains can make a tremendously negative impact on search engine rankings. The "fixed" comment could have been properly assigning protonmail.com with the ranking data for protonmail.ch. This detail was in the previous HN post, but looks to be left out of this one for some reason...
Disclaimer: This is speculation. Take both this article and my post with a grain of salt.
Disclaimer: This is speculation. Take both this article and my post with a grain of salt.