Nonsense. This type of criticism is unwarranted and I suspect disingenuous.

There are lots of contexts in which we can say we would like to see more data. However, when someone is making a point which is a fairly standard one in the Brexit debates we don't need "references". Nor would referring to an article that said the same thing as OP somehow validate the point. There is a place for asking for references, but on a basic comment like this there is not.

Based on the other comments, it seems people are more upset about the perspective behind this idea rather than its truthfulness. I don't agree with the perspective that leaving the EU is a good thing but it is uncontrovertible that a significant portion of the population in the UK agrees with OP's statement.