Microsoft has much bigger problems to address with their first party. I am doubtful they'd be able to adequately support a VR platform. So from their perspective, it probably makes sense. You only have so many resources, and when you go years without major exclusives despite huge buying sprees you can't really manage to effectively support that platform.
I am just glad that we have someone like Sony that can step in and provide a superb platform with a multitude of support by some of their smaller devs and partners.
Sony has spent years building out its internal studios before seeing sustained mainstream success even similar to what we see with Nintendo, year in and year out.
Microsoft was really late to the party there. Ironically they started out with Bungie and Rare, two studios who at the time were probably better or more consistent than anything Sony had with the then exception being Polyphony Digital. Rare's quality immediately dropped off under Microsoft and there was probably a mismatch in terms of culture there. Microsoft's focus on Halo reminds me of countries that are oil-rich and don't invest elsewhere. They used exclusives (short-term and long-term) to buoy them in the early Xbox years. Splinter Cell, Ninja Gaiden, KOTOR.
They probably should have bought Epic or bought into Epic.
But in 20 years in the market, they really haven't developed any of their franchises.
Halo is probably at an all-time low in terms of approval
Forza/Forza Horizon is just what it is
Gears is mostly dead at this point
Fable is going to get a new game but does anyone have high hopes for it?
Microsoft's big success has been their purchase of Mojang and they have a lot riding on the next Elder Scrolls game. And they have a lot riding on the Activision buyout with CoD.
So the idea that they had the bandwidth to really dive into VR at this point is somewhat suspect, but they probably could have and should have partnered with Oculus here on VR for Xbox Series. They're repeating the same mistakes they've made over the last 20 years, which is they'll be left having to buy studios adept at making VR games and franchises, rather than internal teams that have experience with it. That strategy CAN work out, but it has its own risks involved.
Meanwhile, Sony is going to be synonymous with VR on consoles, even as it goes through the bumps and bruises and the Iron Man VRs.
On the other hand, you can also stretch yourself thin by working on different things. The PSP and Vita probably set Sony internal development back a decade. We might still have Zipper Interactive and maybe we still have Sony Bend if it wasn't for the handhelds. Maybe Evolution Studios/BigBig studios could have focused on shipping a better console sku? Who knows.