Immigration is also a big factor in the Conservatives' defeat in the general election. People felt cheated as immigration hit a record high and voted Reform UK, which handed Labour a huge majority despite actually getting fewer votes than at the previous election.
So it's quite extraordinary to see the comments here with zero reflection on why all of this happened. This is the real, dangerous divide between the well-offs in and around London and the rest of the country.
I have read that the two main issues on voters' minds in this American Presidential election were immigration and the economy, so result is not very surprising.
"High" migration likewise had nothing much to do with EU membership, as the government demonstrated precisely by following Brexit with, as you say, record high immigration.
One of the other famous big concerns Leave campaigners had was the cost, which famously became the £350 million a week on the side of a bus. This number was even called out as a falsehood at the time, but it was believed by enough to make a difference.
Remainers were unable to convince the majority that the benefits of EU membership was worth the cost, financial or otherwise, regardless.