Hate to say it, but plates for bicycles make sense. I'm sure people were up in arms when they were proposed for cars, but people got used to accountability.
They don't for exactly the same reason that mandatory cycle helmets don't make sense.
Cycling is good for society, the more people cycling, the better. The reduction in health care spending alone from a fitter society far outway any costs of the few poor souls who die while cycling.
Any barrier you put in the way of cycling up take will decrease the number of people cycling. Society pays the price. We have a natural experiment for this. It's called Australia.
And that's before we get into any of the practical things. Like where do you mount the number plate on a bike? Does my 3 year old niece who's learning to ride a bike need one? What about an 11 year old? etc...
So, while I have to give you 10/10 for trolling, 0/10 for actual logic behind the post.
J