That's fine untill you get a total arsehole driving a wreck at 100mph outside a school. I'll leave it to you to tell the parents of the dead children your zero regulation policy...
Sometimes simple preventive measures , things like checking a car has working brakes before allowing it on the road is the obvious way to go.
Of course there wankers who drive dangerous cars with no mot. But this law insures the vast majority have their car checked for major faults they may be unaware of. That's a good thing