Edit: I'm gonna try and stop mentioning other games after this to. Pretty sure this forum has the common "you shouldnt talk about other games here" rule most forums do, and I have no idea how strict said rule is. So yeah, I'll try
Parents who play games with their kids. Siblings who only have one console. Couple's who don't want to buy multiple consoles so they can have their own screen. It's not as small of a minority as you would think. Just because you don't use it doesn't mean that it's not important. Look at how big the outcry was when other games dropped split screen (Halo 5 comes to mind).
I'm frustrated at how long it's taking too. But I'm not going to be selfish and say that we should get it now even if it means others can't play.
I didnt even bother with halo 5. Only really liked the series with bungie at the helm, but having a co-op campaign was a big reason for me buying halo 4 (as it was one of the very few doing it).
In terms of games like terraria and borderlands, the gameplay is not amazing (not bad mind you, but on consoles it isnt great enough to keep me playing on it for extended periods of time...at least with the current control settings), but I still got through both of them and actually enjoyed them because I could play it with my brother.
A lot of games nowadays like to use the social aspect as a selling point, but for me personally the only time I ever end up being social in games like destiny is when I have to to complete activities like raids. With split screen co-op though me and my brother can both enjoy playing the game together as we dont have to be in seperate rooms and use a mic to talk to each other.....and me personally I find it much, much more social to talk in person then through a mic in the same house.
Not that I dont often play by myself, but in terraria I end up playing a lot of split screen co-op.
But want to know the biggest perk? You dont need 2 systems, 2 t.vs, 2 games and 2 ps+/xbox live subscribtions to play split screen....
Oh, but your selfish enough to keep the majority (I still think we are the vast majority, regardless of your statement) from playing just so you can play by some archaic method of co=op that died in the 2000s?
*sigh* this is why games like halo ditched split screen co-op, because apparently everyone believes split screen is obsolete.
Want to know the biggest reason I love split screen though? Its not because of anything above, but rather because you dont need internet at all to use it. Not that long ago I was not able to use the internet for gaming at all due to the limited ampunt of data I had from my phone plan beimg my only source of internet connection. Split screen games were some of the only fun games I had because I also had limited money (and in turn limited games). Games like terraria and borderlands ended up being some of the games I spent the most time on, but further they were the games I enjoyed the most. I could jump on with my brother and play for hours without getting bored because as most social games like to say, games are better with friends. Yeah, I loved alot of the single player games, but there is only so many times you can play them. Terraria on the other hand, I could play many, many times with my brother without getting bored because, well, I was playing with my brother.
Who seems more selfish now? Me (and others like me), people who are/were not able to play many of the games that require constand internet connections to get the most from them. People who want to play with their family/friends without having to buy another console, game etc, or you (and others like you), who are able to get the most out of any games they play because they have a constant internet they can use for gaming (I'm making an assumption), people who either have friends/family who can afford another console, game etc or just dont have friends who want to play terraria...