Is game length that important? When a game can motive multiple and different playthroughs in its non-linearity?

A game can last two hours to finish, but if every playthrough is unique, does it justify the price of a longer and linear game?

Does it in the case of The Binding of Isaac?

And Left 4 Dead?

Will it be justified the price of Metal Gear Solid V: Ground Zeros? And of Routine?

Maybe it's time to equate a different conception of value.