In the 80's I used to fly light twins on an AOC , the customers were often people of high net worth , cricketers, some pop stars, CEOs etc. 90% was single crew ( there being no legal requirement for two crew - just a request from the the individual company due the HNW of the individual pax).
I can think of at least 10 " friends" who were keen to take my business ( customers) in their rented N registered ( sometimes G reg) aircraft because they could offer what they perceived to be the same service but cheaper ( with no AOC). I often had some heated discussions with them arguing the loophole which they believed exonerated them.
None of them are now pilots.
They were probably correct in some of their views and arguments - who is going to stop them in an N reg aircraft and ask to check their licence and qualification - hardly an FAA rep flying over for the sole purpose ... ( admittedly there was the chance of a ramp check in Europe , but they considered it a risk worth taking - probably a small fine for not having their licence with them ( if they had one).
I am not sure how much has changed - I suspect very little.
This accident has brought this illegal flying to the forefront - will anything change ? - Probably not - there is no oversight