This does seem ridiculous, so I'm going with it just being flat out wrong.
Single player games are like books. Multiplayer games are like sitcoms.
A coop single player style game would be instabad considering that so few people that play cooperative games care about the experience, or cooperate. You'd just have people glitching their characters to look like they were humping Alyx while the squad gets annihilated by zombies and teenage cackles echo "umad" throughout the half life universe.