Outer Wilds' first goal is to immerse you in the world.
Has been the philosophy of all games I've enjoyed so much that I still return to them to this day. I guess it is hard to get immersed in modern games that constantly asks you to make micro-transactions with your credit card to access downloadable content rofl.
True, but in this game it's the sole focus. There's no cutscenes, combats, quest markers to get in the way.
To be fair, most singleplayer games do not require any microtransactions. The multiplayer games, yes, but most do it reasonably well to limit it to cosmetics.