Unfortunately, the Brexit referendum wasn't won on facts and figures like the ones you suggest. A large part of the pro Brexit rhetoric involved ideas like “people in this country have had enough of experts” - from Michael Gove, and the idea that Britain could “take back control” from an “unelected elite”. This type of emotional rhetoric formed a large part of the campaign, especially the idea of "taking back control", which encompassed things like immigration("Let's take back control of our borders"), and the perceived problem of an unelected elite.
This approach, coupled with outright lies (such as the "£350 million a week to brussels" - actually closer to £161 million) was what the Brexit referendum was fought and won on, not on analysis of facts and figures. Specifically in terms of immigration, the Vote Leave campaign simply stated "This puts a big strain on public services like the NHS and schools", deriding any suggestions that this wasn't true as being said by experts, or by an undemocratically elected elite. The 'commonsense' argument - I don't have a job/I don't like my job/I am underpaid. Immigrants are coming into this country and getting jobs. Therefore they are stealing our jobs. - is
was also very attractive.