

I can't think of a single valid reason not to support cross-platform multiplayer, and at least for my groups of friends would GREATLY increase / simplify purchasing so players can use whichever client platform they want. The controller vs Keyboard/mouse debate is just not relevant here, PS4 already supports steam connectivity, and perk progression / achieves have only ever operated on VAC-secured ded servers anyway for KF1 (which I imagine would continue for KF2). If the plan is to support cross-platform, you can give players a choice to only play with others on the same platform or allow mixing, and server-side have the same option.

I would think, at least, for PRIVATE games on your own ded server it would be allowed cross-platform, given the focus on Co-op. I have a lot of friends at this point, though, who have a PS4 and haven't updated their PCs in some time. However, we've been running dedicated servers for KF1 since 2010, and generally only play private games, which I have no doubt will continue with KF2. While I think it'd be great for those in general lobbies to be able to cross together, I can see where at least PS4 and PC players might be separated for games that involve matchmaking.

Forgive me if someone mentioned this awhile ago, but afaik there's no definitive word yet as to whether PC and PS4 will support cross-platform multiplayer.
