This comment will include a lot of spoilers for the yokoverse. Continue at your own peril.
Anyway, just to give you an idea of how little any of this matters to Yoko Taro, here's how his stories have developed:
Drakengard: Ends with absolute apocalypse, total destruction of the world, no coming back.
Nier: Let's go ahead and change the name and say that all the Drakengard stuff has now entered a new dimension. Our dimension! The story technically goes on, and THIS time we'll have the absolute apocalypse of OUR world.
Drakengard 3: Where do we go to continue the Darkengard name? Make it a prequel! Ezpz. Also we already did interdimensional stuff so let's add time travel why not.
Nier Automata: Okay the world basically ended for humans, but who cares? Just make it all about legacy of humans.
You know what, we can do even more already. Why not pepper in some mobile games, like Nier Reincarnation and SINoALICE (yes, this is still Nier universe). Why keep it to games? Let's write light novels (YoRHa, Drakengard 1.3) and a stage play (YoRHa Boys). I am not even the biggest Yokostan so this list is probably incomplete.
My personal take is that this methodology is all very intentionally tied to the main theme of the Yokoverse, which is that no matter how dark and hopeless the situation may become, there is always a future; a new opportunity.