Dismiss Calendar notification popups more easily
This is a really good question - I am bothered by the same issue. I Googled, and found this exact topic, posted here about 6 years ago.
Can macOS have a keyboard shortcut to dismiss notifications?
There's a pretty good discussion about this, and I downloaded the "Alfred" workflow solution since I own the app. The alfred-notification-dismisser by zakyum on GitHub is located here.