I can see why this would be annoying when a project is first being set up, but once things are underway I much prefer having individual emails for each event. The advantage comes when you only scan the subject line for each notification.
For example, we use trello at my day job to track projects and tasks. They offer to send emails either "periodically (once an hour)" or "instantly". Nevertheless, they still fold multiple actions into a single email if they happen in rapid succession, and send an email that says something like "2 new notifications on the board Development". I would much rather see each notification as a separate email since sometimes they are relevant to me and sometimes they aren't.
For example, we use trello at my day job to track projects and tasks. They offer to send emails either "periodically (once an hour)" or "instantly". Nevertheless, they still fold multiple actions into a single email if they happen in rapid succession, and send an email that says something like "2 new notifications on the board Development". I would much rather see each notification as a separate email since sometimes they are relevant to me and sometimes they aren't.