Valve/Steam does not require games distributed through its platform to use their SDK/DRM in any way. It's up to the individual game developers if they set such

Valve/Steam does not require games distributed through its platform to use their SDK/DRM in any way. It's up to the individual game developers if they set such a Steam a trap. Valve doesn't even give an outright monetary incentive to do it. i.e. Valve's 30% cut doesn't turn into 10% if you link in Steamworks. Though one could argue there's an indirect monetary incentive created by locking away all the platform/social features behind a wall accessed through their proprietary library. But last I checked the DRM aspects of that library could be ignored while using the rest of the platform. It does automatically stay updated though, so they could turn Evil and force DRM @ initialization if they wanted, hypothetically speaking.