Hanzo's ult is just to easy to dodge because it's slow moving. Sure it can clear a path but any competent player won't die to it. You can hear it charging, and see it coming. I dont remember the last time I got killed by a Hanzo ult.
Sure, it can occasionally get 3-4 kills but thats if the team is oblivious, or you sit there the whole match trying to line up that perfect shot which is a waste since you could be charging and using 1-2 more.