No, you don't get the correct impression! Penalty marking made the old CAA ATPL exams very hard, together with an even more idiosyncratic approach from the CAA to marking and setting questions for the theory subjects than is displayed these days. The quantity of knowledge required to pass the exams has probably remained more or less constant, and the proportion of that knowledge that is apparently of obsolete topics is still considerable!
The number and proportion of examinees who pass these days is far greater than it used to be.
Scroggs