Just had a team flat out give up

Just played a game as Trynd jungle. Stomped the shite out of the Xin enemy jungle, got early dragon, soloed rift (which my top laner stole and then never used >___<), got each lane kills.

But enemy mid was a yasuo. Our mid was a TF. TF did ok ganking other lanes with his ult. But could not stop feeding the yas. Even after I killed yas 3 times. He then proceeded to give up. Due to that, our Nami support and Lucian adc gave up and sat on fountain as they pushed into our base. I tried to rally people, we were almost even on kills and had 5 of their towers down. But no, "enemy yas too strong, just give up" and then proceeded to flame me for trying to come back and win.

Not sure where this is coming from... but it's becoming a disturbing trend when I'm on a team that is facing even just one fed enemy... people just... stop trying. At all. I don't understand.