Those UK figures are for people who are allowed to work.

The west doesn't have massive shortages of unskilled labor. Quite the opposite: we're losing opportunities for our less well off people to work due to automation. It's a real tragedy for the mentally disabled: they used to be able to get relatively unskilled jobs like restocking and factory jobs, and now just end up aimless. I used to have a fair bit of contact with that group due to involvement in autism support stuff – even 20 years ago this was a big problem.

What's happening instead is unskilled immigrants are screwing over career progression for young people. Eg in Canada, it used to be easy for teens to get their first jobs working at places like fast food restaurants. Now those jobs are being taken by immigrants, giving young Canadians no way to get into the job market. That's an atrocious outcome. And it further depresses birthrates by making it even harder to raise kids.

The numbers don't lie: the world is full of poor countries with average IQs significantly less than the west. Allowing those people into our countries makes our countries worse.