The ball is still in Microsoft's court. Full-stop. Want the ball to be in Sony's court? MS can remove all the restrictions that prevent Sony from being able to really do cross-play, while posting garbage about how Microsoft is so open to it to make it seem like a Sony problem. If you are the one late to the party, you are the one who makes concessions, you don't get to dictate terms to the people who are already there.
Until that time, MS are still the ones preventing cross play, not Sony...as Sony has been open to it for years.
It amazes me just how much credit Microsoft always gets for playing catch-up, post Xbox One reveal.