Bard support in ranked who never used his Ultimate

so what? by the looks of it, he did the most damage and had the best kda as the support

it doesn't look like he was the problem

Bard main here.

Bard ult is one of the most uniquely powerful ults in the game, but it also has among the highest potential to backfire of any ability. It needs to be deployed precisely and carefully.

The vast majority of the time that my teammates complain about my ult use or lack thereof, they are, to put it delicately, fucking idiots. The classic offenders are ADCs who get caught and ping my ult like it would have somehow saved them. I shouldn't have to tell people this, but if you get hooked at level 6 by a Blitzcrank, chances are I won't be able to save you with my ult.

I can't swear from where I sit that the Bard on your team was making an informed decision every time they opted to not use their ult, but clearly the main issue is that your Bard support had the highest damage of the team. No support can win a game when their team (100% comprised of champs designed for damage output, not tanks) can't deal more damage than them. Bard has decent base damage, but it's not like you were understandably shown up by a support Brand, Lux, etc.