I think a key difference is that in Formula 1 there are limits to the types of designs teams can build. To my knowledge that doesn't exist in cycling to anywher

I think a key difference is that in Formula 1 there are limits to the types of designs teams can build. To my knowledge that doesn't exist in cycling to anywhere near the degree of Formula 1. Formula 1 may not be an "ideal" design if you let each team do their own thing entirely. Also F1 car specifications are also designed around their ability to race with other cars. The reason cars look so similar in F1 is because they are mandated to be that way to a degree. But that doesn't necessarily mean it's an "ideal" design. However similarly, cycling helmets are designed and tested in wind tunnels believe it or not.