Remove mobile phone verification
Your requirement for mobile phone verification during registration nullifies any claims you make about this being a secure & private email service. Once I share my mobile phone, my identity is already compromised, no matter what you claim you will or will not do with it. Assurances you give that you do not store mobile phone information are meaningless since such a claim can not be verified. The assumption must always be that any personal information one shares with a website is liable to be compromised at some point in the future. I do not need to cite the countless examples of this happening. I was able to secure my current email before you introduced this requirement but obviously I will not be creating a new account with you until you drop this unnecessary requirement. There are countless other ways you can ascertain whether your system is being accessed by legitimate customers. PLEASE REMOVE MANDATORY MOBILE PHONE REGISTRATION.
If you want to register an account with protonmail.vpn you could donate them 5€ I have done it and it works.
Faisal M. "Low reputation" meaning ANY reputable VPN used by millions of people? Number hashing means nothing to me. If someone at Protonmail wanted to see your IP, they could. And how is that claim of hashed numbers even verifiable from a user's perspective?
Faisal M commented
It's not mandatory, your IP address is likely low-reputation. You can also verify via CAPTCHA from a clean IP. Also they store a hash of the number, not the number itself. Even if they are compromised, the hackers cannot form the number from the hash. Alternatively, you can email them for an invite.