Hello fishtankcreative,
Thanks for reaching out with your question! I’m happy to assist you with this.
If Google says not to worry about it, then I wouldn’t. 🙂
Events come and go, just like some posts and pages. If they are removed or if they don’t exists it will give a 404, which is normal.
If you would like to redirect traffic from past events that are deleted then you can use a redirection plugin to do that for you.
Also I can recommend this article from our knowledge base on this topic to give you some more info.
Do you have any other questions I can help you with?
Cheers,
Andras