EU PPL is not in accordance with ICAO
The EU PPL is in accordance with ICAO; it is the LAPL that is NOT in accordance with ICAO and will be limited to EU.
The safety issues (and that's the only reason for having a licence) are the same for both licenses; establishing dual standards to achieve this is a flawed philosophy.
CAS busts are the result of antiquated PPL training and equipment,
Quite often they are the result of sophisticated modern equipment that the pilot cannot operate because of its complexity. There is no correlation between what you can afford and what you can operate. Any pilot should be capable of avoiding CAS by the use of traditional techniques and Mk1 equipment and not have to rely on equipment that can fail.
the vast majority of new PPLs chuck in flying within a year or two
This has always been the case. People learn to fly to satisfy a desire to do so, and once qualified the level of indulgence falls exponentially. Economics probably plays an important part in this.
most instructors have never been past the crease on their chart.
Most flying training never goes beyond the crease in the chart but, all instructors are required to have completed a 540 Km X-Ctry and the grass on the other side of the chart is not greener.