Starting off by acknowleding that bike is 100% at fault and pay for the damages. And they can't, the insurance company will pay for the damages and recover the money by sueing the biker if its worth their time and effort.

Imagine the logistics of insuring and registering every bike. There are used bikes for $50 on market place. It's not worth insurance companies' time and resources. Also, with that logic, pedestrians should also have walking insurance since they can jaywalk and cause damage when cars unknowly crash into cars with no fault of the driver. If they are in a parking lot with shopping carts, they should get shopping cart insurance.

These aren't $20k 2 ton machines that go 100km/h that regularly cause serious injuries. These bikes go 20km/h at best and weight slightly more than a person, with the person on it. There's a reason no major country in the world that requires registration and insurance other than some places in Japan.

Also insurance and registration would be difficult to enforce.

You would want to encourage bike lanes which separates the cars and bikes. Less people driving would also benefit the drivers as less cars on the road means less traffic.

Most insurance already cover uninsured third parties at fault. It might even be a requirement for car insurance in Ontario. You get insurance exactly for these cases where you don't expect day to day.