While 20% of their population is foreign and their birthrate is below replacement, this economic issue shows why it's a failure. Foreigners are too well integrated which prevents the kind of dynamism that is needed in all territories that boosts the economy. Britain should set the standard.

Britain is setting the standard alright - for what not to do if you value your society.

No, that's just because of Brexit. Diversity alone is not a magic economic bullet.