I
I don’t think anyone has said being British imbues them with superpowers.
But it
is a fundamental part of who you are. Your mate is Polish, your brother’s wife is Colombian (I bet she’s properly fit

?): I’m sure they would say where they were born and raised is a fundamental part of who they are, and they probably (rightly) take a great deal of pride in that. Ask them - I bet their origins form a key part of their identity. I’m sure they would also intrinsically identity you as a British guy they get on well with.
By the same token, as a British bloke, surely you must accept that’s a fundamental part of who you are and how you are viewed by people from the rest of the world? Saying that is in no way making a negative judgement about other countries/cultures, on the contrary, it’s something to be appreciated and celebrated.
I would also like to be part of the EU “for trade purposes”, the reason I voted leave is that the EU’s ambitions are clearly some way beyond that.