Something doesn't add up here.
I think where the confusion lies here is when people get the CPL and IR issued at the same time. That 154 Aircraft IR's are probably people who have attached the IR to their CPL. Ex Instructors mainly.
What would be a good stat from the CAA is the number of IR's issued each year against the number of initial type ratings. That would show a better indication of the number of wannabes floating round.