Citation needed. I seriously doubt your balance of probabilities.
Britain pre-Windrush was on its knees.
Britain pre-EEC was "the sick man of Europe".
Please bring up some actual numbers to back your reactionary talking points, at the very least.
https://en.wikipedia.org/wiki/List_of_countries_by_largest_h...
The United Kingdom represented 6.42% of the world's economy in 1960 (highest point), falling to 3.42% in 2012 (lowest point). It accounted for 5.2% of the world's economy in 1820, 9.1% in 1870, and 8.3% in 1913. England, Scotland and Wales generated 1.8% of the world's GDP in 1600
So the question again is: Do you genuinely believe that this drop in relative output was caused by inward migration, considering all the other historical factors?
I'm not sure why you're coming up with a fictional hair-care product. If you aren't comfortable sharing your answer, then that's fine.
I’m afraid I don’t understand the logic behind what you’re trying to say regarding the relationship of GDP and immigration. Obviously net inward migration can only raise the total GDP of a country. The question of what happens to average incomes is much more nuanced, but there’s a fair bit of evidence that low paid workers can be hard hit in the short term, whereas everyone benefits in the long term: https://fullfact.org/immigration/immigration-and-jobs-labour...
I am not suggesting that you’re a racist or anti-immigration, just that your views on the relationship between GDP and immigration are wrong. Besides that, they do nothing to refute my original point that we should not have different classes of citizen based on race and geography.
Windrush arrived in 1948. That "mass immigration" is literally what brought Britain to its highest point.
Then the rest of the world was de-colonized, started working for themselves rather than for Europe, and here we are.