What you can play now
The released PC 1.0 experience is single-player. There is no current matchmaking, co-op lobby, shared-Nest mode, or competitive multiplayer mode to enable in the standard game. Buying the game today should therefore be a decision based on its solo campaign and simulation systems. Planned features are not part of the present purchase unless they are released later.
What the multiplayer plan describes
The planned concept has each player operating their own Iron Nest rather than several people sharing one machine. That structure could support cooperative missions, competitive scenarios, or both. It remains a development direction rather than a shipped feature. No public date currently turns that plan into something players can schedule a session around.
Do not mix separate co-op plans
A separate same-platform cooperative project has also been discussed with a late-2027 to early-2028 target. That timeline should not be presented as the release date for multiplayer in the current game. Development targets can move, and separate projects can have different scope. Check a future official announcement for the exact product, supported platforms, and playable mode before treating any date as final.