But the social welfare in the UK is far higher as a percentage of GDP and of government spending than every other country in the EU.
That's quite possible; I don't know.
But those benefits should be available to the people who the citizens and their elected representatives want in the country, not whoever the un-elected bureaucrats in Brussels decide should be in the UK.
You were talking trade before and the UK has done a fine job of that over many centuries. They will continue doing so in my opinion.
Citizens and their local & nationally elected representatives deserve to write the rules about immigration.