There is nothing preventing a cyclist from wearing motorcycle gear on a bike. I would never do it though because it isn't practical. But this is precisely the point I am getting at and in fact I do not wear a helmet at all.

As for saying "you might as well ride a motorcycle or a scooter" - you're missing the point entirely. As a cyclist, I don't ride for any other reason than I prefer it.

If you want to say that a car is slower, I would beg to differ. In normal commuting traffic, I blow past the parking lot that urban streets effectively become at rush hour.

Once you go that far, why not drive an SUV? You won't even notice all the scooters and pedestrians you run over!

The reason we ride bicycles is that bicycles are perfect vehicles, and require no "safety gear" whatsoever.

You can wear whatever safety gear you want on a bike. It's just that bicycle crashes are usually so low energy that motorcycle gear is overkill. On a motorcycle, road rash can grind flesh off down to the bone. Nothing's stopping you from wearing a motorcycle jacket, full finger gloves etc. every time you get on a bicycle though.