Pacman was not a game about immersion and realism, Skyrim is (as well as most other modern games) in the sense that we want the characters to move and behave realistically
Pacman is a game though. Refining your criteria of "game" after the fact... Sure I can dig it, I have to cut immersion from use though. It's for a primary design goal in some games> this in not the same thing as simulation or realism. and one isn't a cause of the other. good story telling and music alone can be immersive. and that scene can be fantastical as you can imagine. Immersion is suspending disbelief. Nothing about simulating reality.
There are also many a modern games that do not try to simulate reality as the primary design goal. actually I have trouble thinking of any besides actual sims.. SC2, Spore, FF, tekken, halo, and any adventure game all are much more focused on other elements besides simulating reality.
for example: COD is set up for fun and playability rather than simulation. I can go about presenting may obvious design decisions on that game that are all gameplay orientated. For examples, they purposely set up their physics for playability rather than trying to totally sim RL. yeah they want it believable, but it isn't totally accurate. and they could do so. But it isn't, because its more fun to run faster in twitch shooters than soldiers do in reality.. lol srly it's like the flash. and jumping... damn i need those air jordans!