Probably because the cloud already exists, it has many pros but also may cons, the worst of which for gaming, lag, can't be solved as local will always have a lag several orders of magnitude lower, and because any statement about MS INVENTING the cloud is pure and unadulterated PR BS, btw not only MS didn't invent it, but also MS own cloud is largely based on Linux and Unix servers.
About Google world, cloud is largely used by many Android apps, including multiplayer games, but only a few very efficient ones manage to make the lag not annoying, still moments of horrible lag happen every now and then playing them too.
But essentially, as good as MS implementation could become, there's obviously no reason for Sony to be in discussions about it. Sony can surely better its own cloud, but even in its most arrogant moments it won't do such a ridiculous thing as claiming to have invented it, if they want, they'll better be involved in less unbelievable discussions, articles and PR.