Why would that be the case given MS where still at the time limiting cross play to Win Store games/Xbox and as said by PsyonixYeah, I get it, but if they truly weren't just trying to take advantage of a PR win previously when they spoke about it (like MS is doing now - let's face it, that is the only reason any of this is going public now that MS has agreed) it would seem that they should have already had their policies well worked out in the chance that MS would agree once they began goading them publicly.
Just seems weird to not have drawn this stuff up prior to going public if they were serious.
It was only MS/Psyonix that knew about this before it was announced.