Probably due to the top down management style of Sony, but when both CEOs meet and make such a big public announcement, there's definitely something behind it backing things up.
Personally, I see it as two entrenched players seeing a potential newcomer (i.e. Google Stadia) and realizing it would be better to work together and keep the duopoly going than let a newcomer tear away both their market shares.[1]
It's always better to pick the devil you know, as they say.
Nobody is losing any sleep about Google's vaporous Stadia offering. It is yet another game streaming service, which aren't rare[0] (Sony, Nvidia, and Microsoft already have one). Plus they're starting with little strategic advantage in the space, with most of their early games being limited Android ports.
After Sony, Microsoft, and Nintendo I'd imagine the largest competitor/concern would be either Apple or Oculus (with their new Quest console), Google perhaps next, but that has nothing to do with this alliance. Google cannot even encourage games on a tablet or Chromebook, let alone a TV.
Apple are a slightly bigger threat because the Apple ecosystem already supports larger and richer games, including on tablets and TVs.
A possible scenario is that Sony has been floating this for a while but MSFT has resisted.
MSFT probably agreed to go in giving Sony good terms because they are afraid of Stadia. Not because it’s a threat to their gaming business but because it’s a threat to Azure. Heavy Stadia use means GCP has a high use tenant that pays for their use which they can use to make the rest of their offerings cheaper without losing profit. And that would hurt Azure, which is gonna be huge if MS is gonna live up to its trillion dollar valuation.
IOW they are worried that Google Stadia will be to GCP what Amazon retail is to AWS.
The article says the deal has been in the works for a year, the stadia announcement might have helped finalize it but does not seem like a first cause.
IMHO the deal is mostly coming from the fact that managing data centers is a mess, and MSFT managed to convince Sony they could do it better and for less money.
going by google's track record - even if no one countered google stadia and it enjoyed enormous success, the PM running stadia would eventually leave following which google stadia would be getting the ol' bullet to the head by 2022
google can't into long running services anymore, their company culture has become toxic to it
Personally, I see it as two entrenched players seeing a potential newcomer (i.e. Google Stadia) and realizing it would be better to work together and keep the duopoly going than let a newcomer tear away both their market shares.[1]
It's always better to pick the devil you know, as they say.
[1] https://www.polygon.com/2019/5/16/18628245/sony-microsoft-co...