While it is true that Tracer and Genji have had complaints for most of their active meta life (90% of the game), it was never as simple as them being unfun to fight.
Whenever I see a post about balancing Tracer, it is always based around finding creative ways other heroes could be tuned to help counter her. As it stands, she has very little stopping her from dominating. But her damage has always been (relatively)slowly added up, giving you plenty of time to either damage her enough to retreat or kill her outright. Add this to her limited vertical mobility and that she has no CC, and we find just a very challenging hero.
Moving on to Genji, most arguments that aren’t about how insanely powerful it ultimate is(was) are more about deflect having a hitbox the size of the moon. Sometimes it does devolve in to how unfun it is to fight against a deflect like that, but the problem is being worked now that they finally adjusted the hitbox on deflect. If only they could do the same to Swift Strike too!
So there, the 2 heroes mentioned whos complains weren’t about how they are unfun to fight, but more about how their kits are simply too powerful or lack counterplay.
Dive meta is trash, Doomfist is part of dive. Its literally all he does.
Lets be fair, we don’t really want them removed. But I will say that removing them would be better than having them stay in their current state.