I'm currently storing most of my data in Dropbox, but I would love to move away if Proton Drive could do the same thing. The one hangup I'm having is getting files from email to storage, particularly those submitted via a form on a website. Dropbox allows me to BCC a unique address and automatically save any attachments into a folder.

Info: https://help.dropbox.com/create-upload/email-files-to-dropbox

Alternatively, tighter integration with Proton Mail would be helpful (e.g., setting up a filter or action to save attachments).