I need Apple Mail because a web application (Pipedrive) I'm using links to Apple Mail to send emails (it doesn't link to Gmail app). Thus I want to use Apple Mail to send email. I don't want it to store or receive email. I just need Apple Mail to link with Pipedrive.
As a solution I tried to revoke permissions via Gmail security: https://security.google.com/settings/security/permissions?pli=1 This however resulted in my not being able to send emails via Apple Mail. I also went into the labels tab in Gmail and unticked "All mail" for "Show in IMAP". This has not done anything: