I am migrating away from Proton. In theory they check all marks, in practice they fail in delivering baseline functionality in all categories.
1. The Web interface email is so-so, but the proxy email bridge is really heavy and takes a huge amount of disk space. It also makes my computer start flying from time to time. The iOS email client(very important as they dont support standard protocols) is just useless. The text is rendered like an image which I need to pinch to zoom in and slide across the text. There is no way for the font size to be increased to a legible amount. The images in attachment are not in a carroussel so I need to open1/close1/open2/close2/open3/close3 if there are 3 attached images. In an email client this is absolutely basic.
2. ProtonDrive: It took a long while before rclone was supported and for their web client to be working, "ok". Anyway it is basically unusable as a backup cloud service because it takes forever to encrypt in the browser. I just gave up and have no idea what is the state of sync of my files there. I just moved to backblaze and am waiting for my Proton subscription to expire.
3. ProtonVPN: Good on paper, totally untrusted and blocked by the internet. I can't navigate without filling 10 captchas or just be outright blocked.
4. ProtonCalendar is proprietary and not compatible with generic tools in iOS or linux or Android.
I gave up trying their other services as I just expect them to be as incomplete.
I mean: Email is the thing that needs to work right and every time I need to see some email together with my wife I feel like this goofy person that complicates what for everyone else is one of the most basic tasks in using a computer.
If I could I would just cancel and ask my money back, unfortunately they do not do that.