That's by design, border control was a selling point of Brexit, as brexiters saw only the bad side of immigration. Which to be fair, is no seamless nor without challenges or cost. I suppose the rational is: • Diminish the friction that multi-culturalism and diversity integration can bring. • Free jobs for the local population. • Having to share less of lands, resources, and infrastructures. And I see the point, but i…
> - the UK needs the import/export flow it was used to pre-brexit to keep their current life style.
That is about goods, which are totally separate to immigration.
> - the current british population doesn't seem very motivation to take back the job they delegated to immigration.
Motivation has nothing to do with it. The employers offering these shitty jobs have gotten used to being able to pay poor wages to cheap imported labour. They need to pay more, and the jobs will be filled. Look at the wage growth of truck drivers as an example.
> - the UK education system sucks.
Disagree here. The UK punches way above its weight in terms of high end education institutions per capita (trailing only the US) The UK also has more STEM grads per capita than any European country.