Why does Mac Catalyst never displays a backButtonTitle of navigationItem?

When we run the same navigation style app on iOS and Mac Catalyst, the navigation bar displays the back button title only on iOS as configured.

However, on Mac Catalyst, the back button title is always missing, regardless of the configuration.

navigationItem.title = "Home" // this will display on iOS only, not on Catalyst

or

navigationItem.title = "Home"
navigationItem.backButtonDisplayMode = .default
navigationItem.backButtonTitle = "Hello" // this will display on iOS only, not on Catalyst