If you hold a class Z ceramic, or whatever the cheapest most basic type, the capacitance value starts to drift pretty substantially just from the heat of your hand.

That said I experimented with a cheap X7R 50v ceramic by samsung at C16 and the display interrupt speed did not drift much (15-20hz I think it was) even at the extreme ends of temp that these games would be operated at. The display interrupt does not have to be too precise except maybe in a couple of the really busy games like Mr/Mrs pac you find a sweet spot for the display interrupt or else lamps and displays flicker. Even then you have at least a 20hz window which would be within the worst case tolerance when using an X7R in what I tested.

Caps have probably got a lot better since the late 70s. If bally built that circuit now-a-days I figure a NP0 or C0G type would be specified there instead of the poly chicklet looking cap.