Games are meant to be played in the company of others. Yes, many are built with a single player in mind, but often these are more enjoyable in tandem with friends and family; watching over the shoulder, pointing out items, offering advice and sometimes just helping to share the weight of particularly emotional moments. I wasn't able to finish The Last of Us without my wife there to experience it with me.
I love single player campaigns. I rarely buy a game for it's multiplayer alone. Even when I have, it's been to share that game with friends either across the country or across the couch. That's why I am so apprehensive about the loss of local multiplayer.
When I was a child, having friends over meant playing Street Fighter or Super Smash Brothers together. We'd fly X-Wings side by side or storm the beaches of Normandy. Some of my favorite memories are of playing those games with someone whose hand I could shake afterwards.
I feel that most online multiplayer plays to a different side of us. It's often ultra competitive and even team based modes are less about working together than out-performing your teammates. We see this in most shooters, from Halo to Battlefield. It lacks that distinct touch of coordinating with the person sharing the same screen. I often wonder why I play a medic in Battlefield 3, when I seem to be the only person trying to revive my fallen comrades.
I don't think that most players only want online mutiplayer. I do think many younger gamers haven't experienced much else. local co-op is less an expected feature than an occasional bonus. This is especially difficult when wanting to play games with my family. My wife and I have loved Halo and Borderlands for many reasons, but the ability to play together is tantamount when considering a purchase.
There are still a fair number of games offering local multiplayer, but that number is waning discouragingly every year. My kids are getting older and expressing more interest in playing games. I just want to play with them. As I've already said, so many memories of my childhood are of playing games with friends and family. It would be heartbreaking to not be able to share that experience with my daughters. Consequently, this is one of the reasons I've been more seriously considering getting a Wii U.
I hope that the commitments to local play made by Bungie (although reports on local play for Destiny are conflicted) , Gearbox and Nintendo stay the course. I hope even more that they can influence other publishers and developers to re-embrace this core aspect of gaming. We all want games to bring us together, but it isn't always about spanning continents. Don't forget the gamers withing arms length.