Lets take a typical flying school today with 1 CFI + 2 F/T instructors + 4 P/T instructors (say). Student PPLs can reasonably expect to complete their course with 1, maybe 2 professional instructors and a good level of continuity.
If these changes take effect, economics will dictate that the staff becomes 1 CFI + any number of P/T 'experienced PPL' instructors working for nothing. What will happen to the continuity and standard of instruction then?
If Joe Bloggs can afford £6k for a PPL, he can afford £7-8k allowing instructors to be paid a proper wage. If market forces were allowed to raise pay, there wouldn't a shortage of professional instructors.
Let's not forget a PPL is for many the first step on the ladder to a professional career, not a 'sport flying' license. Let's have PPLs teaching the NPPL and nothing higher.