This farm labour shortage would have happened in the UK no matter what - once Brexit had been finished if the UK followed through on the immigration promises they made to restrict inflows from EU. Don't know how representative it was but most of the "stealing our jobs" crowd was people who don't work from a sampling of interviews they showed on the BBC.

Maybe the "stealing out jobs crowd" are the ones competing for the lower wage jobs. I got the impression that Brexit voters were often towards the lower and of the earning spectrum. While I am for staying in the EU myself I can see why these people don't feel like they get much out of EU membership.