FCB
Good points. I am not close enough to this to know for sure, but the risks must surely ramp up when you have a "more sporty" handling machine, an older slowing reflexes pilot, and one that is not doing a lot of flying and things that keep you current in the areas that matter.
I have no idea how many of these factors affected this pilot, but a spitfire is not a C152, and slow dirty and dragging in at low speed in gusty conditions may not be something practised often if at all. So if a bunch of factors line up, and a wing stalls and snaps out from under you, the reflexes and skills need to be nothing short of 100% there.
As someone who flies a lot, I recognise what I do is a lot of what could be called private/business line flying. Points A,B,C & D and maybe an instrument approach or two, but none of that is much use in an air display environment. A different set of recency is is required.
We will possibly never know for sure, but to any young PPL/CPL reading this, recency is not always about hours in the log book, its about type of aircraft and the type of flight flown.