Its not weird, they blocked it when they thought they had acheived market dominence and were the only ones charging for online play, now there playing catchup again, down the walls come. 

Sony answers with a bit of a non-answer:

http://www.gamespot.com/articles/sony-responds-to-microsofts-invite-to-connect-xbox/1100-6435688/

Basically "we've been supporting PC cross-platform play for years!!" but nothing specific about being open to cross platform play with Xbone games. Maybe if a publisher comes to them wanting to cross the streams they agree, maybe they cockblock the deal like with EA Access. I guess we will wait and see.

Sony already answered it years ago. They've been using cross-play with PC for years and MS was invited to the party years ago. 

And MS had games cross play between 360 and PC years ago as well.

Of course, that isn't the discussion. This is about cross play between PSN and XBL. Well see if Sony follows suit with MS and we get cross play between the two consoles.

To sum up:
All 3 consoles have had PC Console cross play. (and with their own offspring as well)

MS says:
We’re enabling developers to support cross-network play as well. Of course, it’s up to game developers to support this feature.

Sony says:
We would be happy to have the conversation with any publishers or developers who are interested in cross platform play.

So, developers get on it.
And MS, get on with those cross platform Minecraft saves so I can load my ps4 save on PC and iPad :)

It's about cross play between all platforms. The fact that Sony allowed cross play with game devs well before this on a continuous basis and that sony said that they would be cool with this years ago is relevant to this thread since MS is trying to spin this question as they are the first to ask it hence why sony responsed in that way. 

This phenomena is driven by psn and xbla why? , because like you said it's about multiplayer, and that while catered for before the advent of xbox and live,  they pathed the way and on the back of that it  really took off last gen.

I agree with what you said about playing with friends but that works both ways and has been shown with the PS4  now both networks are entrenched to be subject to change , on that subject  even though it might not impact as much , console players with friends on pc may also be a factor if one side doesn't use  it .

On reflection I feel it would have been better put if teigaga said , theres a chance Sony might lose more than they win if they didn't come onboard , rather  than stating it would benefit Sony more than MS .

Such negatively. DX12 and Cloud exists, so where are the lies or disbelief? DX12 only just came out, games take years to make. As for the Cloud, who said it’s not happening? Pretty sure MS/Xbox didn’t.

Be passionate, quality comes with time. Why rush it.

MICROSOFT IS SLAYING!!!!!!!!!

I love how they are puting their Xbox division to their other divisions!

VERY SMART MOVE!!!!

OH! LOL!  XD