Please note. This problem is not present even under iOS 16.0 unless running a firmware version older than 2.1 of the braille display. In cases like the Humanware NLS E-Reader where there is currently no version 2.1, this problem still persists as outlined below.
With applications like mail and Notes where iOS allows for Bluetooth keyboard shortcuts, you can also emulate he command key on a braille display with space and dots 1-7. If you wish to create a new email, for example, you could thus press space with dots 1-7 followed by n to use this shortcut on a display. This does not impact users of the Mantis.