Did you actually tried to launch the game? What error did you get? What game was it?
Steam launcher is not needed unless the game is programmed to fail if it doesn’t detect steam, not all games do, it’s usually a sign of a badly programmed game. Also the game might have had other DRMs.
But for example grab Crusader Kings or Stellatirs which tries to use the steam API bit if it fails it just keeps going without, and you can copy it to another computer and play without steam installed.
Did you actually tried to launch the game? What error did you get? What game was it?
Steam launcher is not needed unless the game is programmed to fail if it doesn’t detect steam, not all games do, it’s usually a sign of a badly programmed game. Also the game might have had other DRMs.
But for example grab Crusader Kings or Stellatirs which tries to use the steam API bit if it fails it just keeps going without, and you can copy it to another computer and play without steam installed.