If you are looking for cute and simple co-op game check out Squirreled Away. It is cute open world adventure game. Fun and chill game to play as co-op. The game is pretty simple and short, but is perfect for the gameplay experience it tries to achieve. It was fun alternative for competitive games that I usually play.
Pitch:
Live your best squirrel life. Explore, gather, craft, and build incredible treehouses in acres of beautiful parkland. Scurry across lawns, up trees, and leap limb to limb solo, or up to four friends can play together in co-op. Endless summer days of adventure await.
I guess the scope was too ambitious. Economy is not doing that well so AAA studios don't like to take any risks. Both this and Blizzard's survival game was cancelled. It is sad that so many developer hours are wasted on these projects and we get nothing out of it. It would be amazing if these games would get released as open source for someone else to finish it.