The problem isn't that people don't try, exactly. The problem is that the ones that try are always on the other team.
I played about 15 games today, and I had maybe 3 my team wasn't a bunch of chuckleheads doing stupid shit. Yet time after time, the enemy team had their shit locked down. Triple tank backed by Ana and Lucio or Zenyatta, Soldier and Pharah being buffed with an mercy that flowed out of range every time, Reinhardts that knew what the fuck they were doing. I think I saw maybe 4 teams that weren't operating like a well oiled machine.
I feel like a conspiracy nut, but there are days, and this is one of them, where the game just says "You are going to lose today. Every time."
Edit:
My life
Edit 2: jesus, why am I still playing. I dropped 300 points, this should be like my 8th loss in a fucking row, and even in this low, pathetic rank that I am in, competent players do exist...but only on the other team. seriously, why do I get 1 healer and 1 tank, while the other team has a soldier who maintains the highground with expert markmenship while Mercy buffs him? Why do I have to go up against the Ana that combines ults with her team every time?