Unless you are naive enough to assume that ProtonMail is incapable of logging IP addresses (in which case they'd be incapable of serving HTTP requests...see the problem?) then they can log. And they most certainly aren't going to declare independence from Switzerland and refuse to turn on IP logging when required to by law.
Whereas with E2E-E, they actually are incapable of turning over readable emails.
Unless you are naive enough to assume that ProtonMail is incapable of logging IP addresses (in which case they'd be incapable of serving HTTP requests...see the problem?) then they can log. And they most certainly aren't going to declare independence from Switzerland and refuse to turn on IP logging when required to by law.
Whereas with E2E-E, they actually are incapable of turning over readable emails.