I agree it's convenient for customers, but it's a lot more convenient for certain customers specifically. Mainly, the ones who primarily game on the smallest of the gaming ecosystems. They're the ones seeing the most of the benefits.
And yeah of course it's always about money in the end with these companies, this is just an instance where that's the case being shown by Microsoft and they're using soft, friendly "pro-consumer" language to dress it up. Ongoing talks over the ABK deal are what are fueling this, they're essentially forced into this approach if they want this type of massive acquisition deal to be approved.
The thing with the Elden Ring deal, it actually isn't GamePass-related (Bandai-Namco would never probably allow that); it's more like you just get a free copy (you can choose Elden Ring among other games) when you buy a Series S. What's interesting is they're pushing this in August, and in territories like NA, where I'd assume Xbox are selling the best.
So either the numbers aren't looking right and they need a push, or they're afraid the numbers won't be looking right as Sony increases PS5 supply even further and big games like GOW Ragnarok start hitting in the Fall. So if MS are hoping to maximize Xbox Series sales in some of these territories, it's between now and November I would guess.
I do hope Sony are doing something with Arc; maybe with Sony's partnership with Disney-Marvel, they and Arc can work on a new Marvel-based fighting game. Arc System Works have already come out and said they would like to work with more licensed IP to expand their reach; Capcom probably isn't touching Marvel for a LONG time thanks to MvC: Infinite's failure, and the only other devs that could make a new Marvel at least as wild as Capcom's are Arc System Works and SNK, but SNK are squarely focused on their own IP like KOF, SamSho and Garou/Fatal Fury/Real Bout.
Also really hoping DokeV turns out super good, so much promise with that game especially since it's not an MMO or live-service title. Sony would be very dumb to not at least try investing into that talent as a majority shareholder if the game is shaping up well and they just need some more funding. Can't let opportunities like that slip by.
Thing is it always starts with "this benefits the niche/smaller games", that's how it gets set up. But the end goal is never to end there.
Like
@IntentionalPun has been saying, cross-play in itself isn't an issue for gamers specifically. In theory it means we get to play with more people. The problem is moderation and security is not equal across platforms. Cheating is RAMPANT on PC and that can affect the console experience for console players. When companies like Microsoft force cross-play on games to generate large-enough pools to cut down on query times, that's a problem.
That's all aside the other things I was talking about :/