Do adc mean anything anymore?

So my adc was so fed, my MF was 6 2 and like 2 assists with 40 cs ahead of the opposing Cait. We got our tower and started to roam to help lanes. Well while we got fed top fed his ass off to a nasus. Come late game my mf doesn't do shit to the nasus. Actually it was so bad that she just fell off and the 0 9 cait got carried hard. Oh and my mid laner was fed but somehow two fed lanes lost against a fed nasus.....which in turn snowballed the rest of his team. How the fuck does a fed adc not mean anything anymore. Taking a break from this stupid game.