Can't "Enable Messages in iCloud" on Mac

See the articles https://support.apple.com/en-au/guide/messages/icht5b5d1e63/mac

https://support.apple.com/en-in/HT208532

macpersona wrote:

On my Mac, in Messages >> Preferences/iMessage, I don't have an option for "Enable Messages in iCloud" (i.e. this menu item is literally not present). Why is this, and how do I enable messages in iCloud through my Mac?

What version of macOS are you running?