In galley view, at the very beginning of the score, the player names are displayed. If the player has more than one instrument there is no indication of the instrument so you have to guess which instrument is in which stave.
When you scroll to the right Dorico show the player and instrument name if the player has more than one instrument. For only one instrument Dorico doesn’t shows the instrument name.
Yes, but my point is, that in the case of only one instrument for the player (in my opinion) the instrument name should also be displayed after the player name colon-separated as it does for multiple instrument per player.
Since the final user of the sheet music will never see galley mode, it would seem a simple solution would be to preserve instrument names while composing or engraving and only change the staff names to Player names before publication or by keeping a separate display layout containing Player names from the working layout used while working on the file.