One basic stat that highlights the issue is average solo times. When I started 5-8 hours was normal, if you took more than 10 the CFI got involved, now it seems 15+ is normal. A lot is the distractions from basics in the syllabus, lack of practical knowledge by the instructors and so on. Sometimes I think of the phrase "the road to hell is paved with good intentions", which sums up the regulations that have been implemented to improve standards, but has had the opposite effect in that it over complicates something that is very basic.
Aviation is something that has simple rules of survival but over complicated regulation, the two don't match. The problem is getting back to understanding those basics again in the early stages. Faulty foundations and the whole thing eventually fails, no different in teaching techniques to building a tower.