Been looking through this post.

My thoughts.

Any road death is a tragedy especially if it is caused by vehicle faults.

But how many of us who enjoy our home DIY would be aggrieved if we were prevented from doing our own repairs and improvements.

I would expect a good vehicle technician to be capable of some wiring and pluming if they are prepared to research the relevant regs and techniques.
I know some tradesmen who are very capable with car repairs, its about knowing your own limitations.

I would imagine that the people who really are incapable would continue whether there was a law preventing them or not.