Which is based on the absolute fantasy that giving a nutter a fiesta instead of a Porsche will stop them killing someone.
It's fantasy.
I am not sure you are worth the effort but sorry it is not fantasy.
The fact that the car can do 70 tops instead of 140 is not really the issue. Everyone else on here sees this but it passes you by.
What we have is a number of things - cars that do 140, lax speed control on our roads, cars sold as "sport" models with all sorts of racing attributes, cars that generally go much faster than we can safely use them at on our roads, sold to use on our roads. a general mood of our roads being somewhere that you can act out or buy into the world of motor sport.
People buy into this world and act accordingly in it. This is deemed acceptable up to a point.
Changing just one aspect will not make much difference. It all needs to change. But if the whole attitude to driving was changed then the way many people drive on the roads will also change.
Is it a fantasy? Well no, there are lots of examples of how we can change the attitude to something. 50 years ago drink-driving was widely accepted and practiced. The
attitude to it changed and it became unacceptable. Laws came in to back up this change.
Bull bars were suddenly frowned upon and most drivers took them off.
Before seatbelts were made compulsory they were mostly ignored but now although law there is almost no objection to them.
Cycle Helmets are mostly now accepted even without legal enforcement.
Smoking has gone from the done thing to be fashionable to mostly the pursuit of seedy old men.
So with a bit of a nudge, the attitude towards driving can change to remove the association with motorsport from driving on the public road. Yes it is a bit change but it certainly can be done. You can change the nutter as well as the car he drives and yes- the change may then mean he will not kill someone.
