Hi,

Our local taxi licensing authority (Bucks C.C.) has its own annual taxi test which involves wheel removal etc.. Obviously this isn't country wide.
I'm sure there are exceptions to the rule. My main observation is that I just don't see the death traps when I'm testing nowadays compared to 20-30 yrs ago.
If cars are still driving around in very poor condition in some areas, the annual MOT only appears to prevent this in the short term.Maybe a couple of months immediately post test.

Tom W