I can say that as a PC game pass subscriber, it is a good service for discovering games that you can then get on steam later. Occasionally it bites you by hosting games that you already bought here, like right now, but as far as problems go that is a pretty good one.
Some games are better to buy despite having the subscription than others. Being low price and highly tweakable, Valheim is definitely one of the games that are.

I must say I'm a little surprised though. With the current trajectory the game will still be nowhere near from leaving early access by the dates that were given. In fact since when did naming dates more than one or two weeks ahead become a good idea again?

Another thing I'm not sure people are thinking about. Being a mandatory extension of the xbox ecosystem since the launch of the 360, I wonder if this will in any way push the devs to decide on achievements that should go in the game? Not that I care for achievements, they are just a shallow sales tactic that is at its most effective when it overrides your own interpretation of what it means to meet a milestone; but if their is pressure to implement them by fall then I wouldn't like the devs boxing themselves into gameplay decisions based on those prematurely.

As for the console exclusivity, not branching out to Playstation, I bet we could look at past decisions from Sony and make some guesses, and at least one of them wouldn't be far from the truth. Just as possible is that it was purely on Microsoft's initiative, as they have been exceptionally aggressive about either partnering with or outright buying talent since they got the head start on these 'pass' type services. They landed on something huge, and with the correct foot before anyone else, in a way that is reminiscent of Valve's initial success with digital distribution all that time ago, and they know it. They're not going to stop until they are convinced that their lead is astronomical. Sounds scary. And I'm paying them.