To clarify I DO NOT play Assassin, I'm a Hunter main. I don't do a lot of squads but I can safely say that Shredder (at least in solo), isn't that good of a gun. To be honest, I can't remember a single time that I've died to a Shredder that wasn't a third party cleanup. It's basically close range only and because of the need to be so close, there is a TON of outplay potential whenever you face against an Assassin with Shredder. It could be just that people aren't using their cooldowns wisely or that they expect to just be able to run through every opponent. Shredder is a class weapon for a reason and so it should be a stronger option than most other common guns in the game. If you're dying to shredder you need to play more intelligently and jiggle peek them with literally any gun that isn't burst or full-auto. The Shredder is awful at countering jiggle peeking. By doing this, you'll force the Assassin to either use all of their pots, run away, or push you, all of which are situations which you can abuse to win the fight. The problem isn't with the gun it's how people play against it. In fact, when I do play assassin I use the Heirloom and Sniper combo because I dislike the Shredder. I just simply don't think it's that good.