Howdy Ben!
That might help prevent Google from indexing new pages, but the old ones will still be in their results. If you wish to hide anything from Google you can do so by adding a robots.txt file to your website. Next time Google indexes anything on your website they will look for this file, when they see it they will remove any pages you’ve told them to. If all of your events are in example.com/events/, then put this in your robots file:
User-agent: *
Disallow: /events/
Disallow: /event/
Does that all make sense? Will that work for you? Please let me know.
Cheers!
– Brook