Company wants to make as much money as they can from you.
Supply and demand. 60m copies of Mario Kart sell at full price, why would they sell it for less. Other companies discount their games because demand drops, not because they are kind.
I don’t know what you mean by overpricing.
The demand is either there or it isn’t.
Nintendo’s efforts have been as good as anyone’s as far as I can tell? GBA worked with DS, DS worked with 3DS, Game Cube worked with Wii, Wii on Wii U - not sure what the issue is.
Less than half of the original Xbox’s games worked on Xbox 360 and the Xbox One only announced backwards compatibility in June 2015.
PS3 ditched backwards compatibility and the PS4 had nothing.
You can’t currently emulate Nintendo games?