A few years ago, with the help of Microsoft and Xbox, crossplay became the norm for multiplayer games across the industry. Sony famously pushed back on the feature before PlayStation eventually hopped aboard, but nowadays, it's pretty much a standard in most big multiplayer games. To be honest though, I think crossplay has gone a bit too far when it comes to PvP experiences these days, and Microsoft has an opportunity to change course a little bit in the coming years - which it should absolutely take.
Let me explain. Crossplay between consoles is fine, because the vast majority of players are using a similar input method to play; a controller. However, with the introduction of PC players into the mix — bringing their mouse and keyboard controls along with them — you inherently have an uneven playing field, especially in first-person shooters. This isn't anything new, it's been going on for years now and lots of folk have brought the issue up, but Microsoft is now moving into an era where this doesn't have to be an issue anymore.