I, like most other "rotorheads", am acutely aware of the consequences of mast bumping and separation.
Once again you have to discriminate between pilot failure and aircraft failure in order to establish defective design. You have not done that.
I also dispute the idea that airplane wings don't come off. They do. Tails also.
Occasionally it's a plain structural problem (eg. corrosion, cracks or bad glue).
Usually, and tragically, it is a consequence of improper flying. Either g overloading, as in aerobatics or flying into thunderstorms; or the infamous graveyard spiral (as a consequence of control loss in instrument conditions).
A similar and sad state of misflying equivalent to misflying causing mast bumping. Also a case of exceeding the approved range of g (-ve).
Sorry Lu, you MUST prove that the aircraft is at fault, NOT the pilot. Rational thinking demands that, regardless of interpretation of regulations (and lies, damn lies and statistics).
The statistics you have presented not only do not show that the aircraft design is faulty, they also suggest that the Robinson R22 is not at all far from other types in similar roles, RW and FW alike. They actually support the assertion that the RW design is safe.
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More volts, Igor