There has never been a factual or rational debate or discussion about the pro's and cons of immigration, although you could say that about so much of our politics.
No politician has really been brave enough to explain the benefits, it's so much easier to assume it is self-evident and that anyone asking why is a bigot or a racist.
The idea of immigration has never really been sold to to the British public so I can understand why people who are not extremists have their doubts. I would like to be better informed about the facts and figures but when everything around it is so highly charged I can't see how that can ever happen.
I do think the whole boats and illegal immigration is a bit of a distraction in that less than 30,000 came over by small boats, compared to legal immigration of 685,000. The vast majority of immigrants are legal and have come for work or study, with the biggest number coming to work in healthcare. Without them the healthcare sector would be in even greater crisis
One interesting side effect of Brexit seems to be that EU immigration is now negative and all the new immigration is from outside the UK. So for those that care about these things we are seeing a lot less white immigration and many more brown faces, which is the opposite of what many Brexit supporters would have expected.