When pigeon flies into you in real life, the worst that can happen is you're a little grossed out and paranoid about contracting a bird flu. But in most 2D platformers, birds spell certain death. Ravens, hawks, eagles, chickens, whatever--these feathered menaces have a penchant for dive-bombing into you on sight, like you were wearing an outfit made of 100 percent bird seed. Even more strange is the fact that, when the bird makes contact, more than a few video game protagonists get thrown back like Muhammad Ali just gave them an uppercut to the face. The force of this impact usually results in you plummeting to your death.
Yes, it is hypothetically possible for a bird of prey to kill a person; those talons can get mighty sharp, and if they puncture your jugular vein, that's pretty much a wrap. But for that to happen, you'd have to literally stick your neck out--instead of doing literally anything to protect your body, like turning away from a lunging creature. If birds were as dangerous in reality as they are in games, Earth would have an exclusively avian population.