a 320x200 6bit color depth wasn't exactly a pleasure to use. I think the games could double the res in certain mode (was it called 13h?)
Games used either 320h or 640h resolutions, 4 bit or fake 5 bit known as HalfBrite, because it was basically 4 bit with the other 16 colors being same but half brightness. The fabled 12-bit HAM mode was also used, even in some games, even for interactive content, but it wasn't too often.
Btw I was a teenager when those Denthor trainers came out and I read them all, I loved them! They taught me a lot!