On this website, this only happens for actions that require entering your email address anyway.
> For every transactional email I need to send out - registration, account recovery, and email change verification - the user always initiates this by submitting their email, and it will at that time be available to the backend to perform the needed action.
So this only works if you only use the email as a username. No way to notify the user of things like ToS changes, security issues, notifications from the service, etc.
Some services don't have the desire (or need!) to send out generic service notifications.
For ToS changes, it's often enough to display them to the user when they first log in after the change. That's how many mobiel apps handle it already.
The security notification thing could be an issue though. Doesn't seem to be necessary per the GDPA but it's probably a good idea to communicate security breaches.
