According to the RAC it takes 23 metres for a car to stop doing 30 mph (48kph) and 12 metres doing 20 mph (32kph), not sure it would be that length on a bike.Both travelling at speeds of 40Kph or more???? What anecdotal evidence is there of that?
If one even assumes they both have the same reaction times (see previous for why I think a cyclist might be even slightly more reluctant to slam on their brakes than a car driver at that speed), four good tyres with modern braking systems are more likely to stop without incident imho.
But I'm very willing to read/see even the anecdotal evidence you have to the contrary. Thanks
While the brakes on a car are undoubtedly better you must take into account the weight of the car, you are the engineer and doesn't momentum equal mass by velocity?

Stopping distances made simple | RAC Drive
A car’s stopping distance is an important part of any learner driver’s theory test. Read here for the RAC's complete guide.