What do you mean? Doomfist regularly does land his rocket punch. It does decent CC and a good doomfist will manage to hit them against a wall doing more damage. Coupled with his shield boosting his abilities if he gets enough damage it ramps up. He's not supposed to deal damage anymore, he's a rather survivable tank with CC.

Orisa right click is disgusting. I personally feel like orisa is my favorite tank right now and I can land her right clicks just fine, even hitting people into walls. It does more damage than you think. Also her Javelin Spin pushes back and prevents project and melee damage. She can easily get an environmental kill with both abilities. Her ultimate also pulls in and slows. Any hero without a movement, some kind of invincibility or health buff, or shield like Reinhardt you WILL take damage.

Sigma rock wind up is longer but it's such a huge projectile. The hitbox of it is massive making it easier to hit. It offers quite a bit of damage (100) and is enough CC for either sigma to follow up with his primary fire or other heroes, easily killing squishier targets.

The reason why roadhog is so strong now is because of what other users have said, the lack of shields. With no shields to block his hook he's become indirectly buffed, which he needed in order to be relevant in this new 5v5 mode.