Before 2016 I would have said the second part. The shite people have been spouting under some flag of "our identity is under attack" since then makes me 100% believe it's the first one. Don't forget that Neil Warnock, himself a man who's been involved in football for decades and who signs many players from the EU and further afield said:
“I can’t wait to get out of it, if I’m honest. I think we’ll be far better out of the bloody thing. In every aspect. Football-wise as well, absolutely. To hell with the rest of the world.”
I'd love to know how he thinks it'll be better football wise to be out of the EU