Numbers v12.2.1 on macOS Monterey still shows Send a Copy in the File menu, or as an optionally installed toolbar item. With Ventura 13.0.1 and Numbers v12.2.1, there is no original Send a Copy functionality. Rather, the File menu > Share… menu item defaults to a Send a Copy selection, you choose Mail, and it attaches a .numbers document to the outgoing email. There is no other attachment format option.
For a Numbers v12.2.1 on Ventura situation, one can manually export to Excel .xlsx and then again manually attach that to an outgoing Mail message. Or, use the automated process in a Ventura Shortcut which I documented here for a one-click solution similar to Send a Copy > Mail > {format}.
after upgrading to Ventura I can no longe… - Apple Community