What needs addressing is that the vast majority of UK PPL instructors have never flown past the creases on their map.
In turn, they impart a similar level of expertise onto their students.
Which in turn helps to ensure that the vast majority of PPL graduates find the piece of paper next to useless (beyond the Bembridge cafe burger run) and chuck it all in within a year or so.
Which in turn helps to ensure that the training apparatus is almost never questioned - who is going to question it?? There isn't anybody around to question it.
And those very few who did drag themselves out of this dead end, bought their own plane (or into a group) and fly for real don't hang around the training environment anymore, and don't look back.
Quite how one would achieve this improvement within the present industry vested interests, I don't know, but it's pretty obvious that EASA doesn't either.
The problem is that there is no objective measure of the "product quality". The schools have no business objective, other than to sell hours, in their planes, with an instructor in the RHS for as long as possible.