I did go in details in another comment so I won't repeat myself because that comment is LONG.

But a nation couldn't ask more than a working age adult where you invested zero in education and health for 20 years and suddenly pay taxes with none of almost no benefits.

In the UK, which I raised numbers due to the discussion going on in there, visa workers generated yearly 12 to 20 Billions in direct taxes and fees and they use 4B in health (which technically they paid in fees a combined value of 6B upfront If my numbers are right)

But the real numbers lies on what other revenue they generate. It is estimated in my calculations that +50B-70B pounds are from immigrants on UK with a working visa.

That's no amount to shy considering about it is 8M people in that specific situation. And remember that none of them had to have their education covered by the government.

Someone in the other comment said that 8M British people would generate more taxes than that, but I did not find evidence of that. According to the public consultation documents UK gov released about immigration a couple of years ago, about 10% of the immigrants are responsible for more than 35% of the taxes collected. Hence the suggestion on curb immigration considering the salary range which might make sense or not depending on where you stand on the topic. I have no horses on this race and my impression as an outsider who just likes analysing data is that it seems as much of a claim as saying that EU took more money from UK than what it put in which turned out to be mostly incorrect.