Proton’s pricing is really frustrating for me because I want to buy upgrades to only a few services like Pass and email. Your only option on their service is to select either Pass or Mail. You cannot buy both and you will be downgraded on one if you try to buy the other.
They really haven't improved Mail in a long time now. Still can't use your own keys, still can't have a clean unmangled export, still can't send using your own keys.
It's almost like Protonmail is intentionally hostile to key management outside of their control.