Yeah 95% of the plays of the game are either Bastion hiding in a corner shooting people or ulting and shooting people.
I managed to pull off a Play Of The Game as Lucio, but I had to go full offence to do it. With Torbjron it's easy. The algorithm seems heavily biased towards heroes that can get a quick succession of kills, which turret classes excel at. I know it's harder to evaluate the contribution from support or utility classes, but it's pretty lazy design to just measure multi kills.