Having seen the FI revalidation 'assessment of competence' requirements (which now take an entire day, it seems), it doesn't surprise me that so many people drop out of flight instruction.
I suspect even more will now give up once the 6 year point arrives....
Particularly if they're also FEs who now need to attend a seminar every 3 years in addition to the other requirements....
So glad I gave it all up; thanks to EASA, it all became too expensive and rule-bound. Which killed off the enjoyment.