I'd consider it akin to something like an RTS or a tower defense game where you are stuck in one spot managing something. Part of what makes it good is that you are stuck in one place with only a few means to defend yourself, and multiple things coming after you.
For instance, in the first game each of the animatronics behave differently, so you have to learn to check certain things on the cameras, turn on lights, close doors, etc. The reason they say "multi-tasking gameplay" is the fact that you can actually only do one of these things at a time. You can't look at the room where Foxy is hiding while checking to see if any of the other animatroncis are waiting outside and you are inches away from death.
