Anecdotal but I feel like Brits are really big on emigrating or atleast working abroad. There are a ton in the US, Germany, UAE, Australia etc. And they tend to do very well outside the UK.

Indeed. Most of my friends no longer live in the UK. Even "average" friends from high school live abroad. I don't understand why people stay. What happens to a country when all those people leave? All those people with a mind that is capable of seeing a better future and acting on it? Who does that leave? Bunch of people who wave tiny flags and cheer a monarchy.

Its not exactly the same situation but I'm from the UK and live in Poland (because I'm a scientist and brexit happened). An enormous number of Polish people left to work all over Europe and the world since the end of communism, and I think its mostly been a massively good thing for Poland.

Most of the Polish people I know who lived abroad and have moved back to Poland have brought skills, often highly educated children, relatively large amounts of money, and what I would describe as an international forward thinking attitude (i.e. they aren't voting for PiS).

Its not inevitable that a lot of young people from the UK moving abroad is a bad thing for the UK, as eventually a bunch of them are going to come back.

That said all the flag waving bullshit I see the UK doing does put me off returning.

They are, the US is just insanely strict with skilled migration.