My iCloud calendar is not showing macOS calendar entries

The title says it all: My iCloud calendar is not showing macOS calendar entries.

My MacBook and MacMini calendars are the ones I usually make entries on. I also have a Google Calendar. These all work fine - every calendar displays the same info. But going to my iCloud calendar shows no entries at all. My macOS settings allow my calendar to be stored in iCloud and I do have iCloud+.

My AppleID is an email address of a domain that I own and the domain email points to my iCloud.

I must be missing something very basic since it just seems crazy that my iCloud calendar does not show what I've entered in macOS. iCloud mail and the macOS Mail app work together nicely. Please advise.