I didn't do anything about this, because I expect any commercial service to log IPs at least for a short period of time to fight abuse. I'm using this service because I don't want the service provider's staff or someone that hacks their servers to be able to read my mails. Ideally I would like to also have privacy (through E2EE) when e-mailing other PM users, but I'm not counting on that. As the Tutanota case shows, such secure e-mail providers can be forced by law to intercept e-mails.