So the meta-conversation is: why was (is?) installing and running a game so difficult? Why did game-makers suck at that, creating a billion-dollar opportunity for Steam?
But then you may ask, well if Apple has such a standard for everything, why not everything just conform to that and we make everything easier... It's not that simple see: https://xkcd.com/927/
It's not that installing and running a game is 'so difficult' it's that you're expecting it to be as simple as everything else you do in your Apple ecosystem. Because that's how Apple wants it. It's entirely a perspective issue forced upon you by the ecosystem you use.
The end result for all this is all the jokes we see about children expecting everything to be touch screen, or having no idea what to do with a controller when they see one. As humans we adapt to our environment, but if we're always forced into the same systems, we start to expect every system to work that way and we stop adapting.