Not to marginalise your lived experience, but there is a distinct psychological difference between farmers - who tend to live more isolated lives - and your typical inner-city Dave. You can't judge them the same way at all as a city Dave has to live alongside the immigrant.
All I am picking up from you is that you seem to think ordinary people who worry about immigration are never going to change and not worth talking to. I have seen Southampton change drastically during my lifetime - but if I had lived in a nice suburb I wouldn't have noticed. There is a real disconnect between all my leftie friends (who are all middle class) and myself in the way we think about the working classes. I seem to have a lot more understanding of their viewpoints, where they talk way too much about people "who don't know what is good for them". Ok, lords and masters, we better cede the vote to your fine selves so you can save us!
Heh, I almost certainly qualify as working class, as do most of the people I've maintained contact with over the years...I'm a long time out of my ivory tower. I've had the exact same conversation with someone I work with about his fears about mass immigration a minimum of 500 times over the past decade I have been at my job. I can mollify him for a day, or a week even. But no, I cannot change his mind. Because what drives it is not the particulars of the numbers of immigrants or a careful cost/benefit analysis, it's a visceral fear that things are changing. This despite the fact that his daughter-in-law was born in China, and the house he lives in with them was purchased by her family ("that's different", apparently). He has a university degree and is hardly incurious, but that gnawing at the back of head doesn't go away.