I still don’t understand what Discourse notifications are.
First, the user menu displays a long list of events, which you can’t clear.
There’s a “dismiss” button, which doesn’t dismiss anything, just marks all items unread.
This behavior makes it really a log, not a notification list. This is also inconsistent with how notification system work on other platforms. There’s always a way to clear the list, and to choose which events should trigger a notification.