It appears to me that there are people/groups around with enough money to buy and operate high performance aircraft which were just not around in private hands 30 - 40 years ago.
The tragedy at Shoreham has brought an unpleasant wake up call to the regulatory authorities where regulation and enforcement has, unsurprisingly, not kept pace with the changing world.
From a link posted earlier referencing the English Electric Lightning crash in South Africa I dug out the previously unread accident report. It was quite staggering how the aircraft had been operated and maintained in what appears to have been a cavalier manner with scant regard for the regulations and little oversight by the South African authorities. The price was a crash although only one person was needlessly killed on that occasion.