This all goes back much further and deeper than non-dom media barons, though have it your way if you will. I don't swallow any of it, much as I may feel contempt for media barons, non-dom, tax dodging or otherwise. It anyway makes little difference to my point, and that is that the politicos here and abroad refused to acknowledge and respond to the rising sense of unease, and they did so repeatedly and consistently over many years.
On the matter of agricultural workers, I spoke to a farmer friend the other day - he too is finding it very difficult to hire workers. The reason for the shortage, as given by the agency he uses, has nothing to do with Brexit. It is because the rising economies in countries like Poland are now offering job opportunities and pay rates that compete with those on offer here, so there is simply no need for them to look for work elsewhere. On this matter at least, the anti-Brexit propaganda conceals a more prosaic truth.
Incidentally, there are apparently more people originating in other EU member countries living in the UK now than there were in June 2016.