In the last decade no one has died flying an approach in IMC in the UK (although one CPL/IR in Oxford came very close).
A number of people have died flying approaches outside the UK (but there is no comperable IMCr population). In general, those have been approaches in and around mountains (which for the most part don't exist near UK instrument approaches.) This goes back to a very big safety feature of the IMCr - its limitaiton to UK only - on most UK approaches, if you use 600 ft as your MDA, you can be 10 miles left or right and still live.
I think the main reason for the differenc in PPL/IR and CPL/IR is that the whole TK structure was designed around commercial training and they 'forgot' about PPL operations. The CPL exam (as I understand it) is actually the ATPL knowledge (ex. MCC).