I threw that in there to be cheeky.
The reality is that Microsoft is simply too greedy to even thinking on releasing their triple A games on Steam. They want all the money, so simple.
No 30% cut to Valve. Just look at the price of Quantum Break, 70 for a PC game, a PC game which also launched with the lacking of basic features.
They are pricing those games like that because those ports, I believe, are done with a very small effort and amount of money, they are like "Ok, if people REALLY want our games, they will buy for the price WE decide, even if it's insane."
This is the reason the Win10 store is a giant fiasco: the price, the fact Microsoft wants (ideally) fully control their titles forcing the UWA thing, the draconian way in which you need to download a game (I'm still unable to download Killer Instinct, despite being on the latest Win10 build).
Win10 is an announced failure, if Microsoft won't change their strategy soon, it will be dead in a couple of years max, if they don't stop supporting it before.
Win10 store is following the same strategy of GFWL at launch, some PC ports, Microsoft trying to make PC users pay for Gold, and than the "abandon the ship" thing.