Its interesting that they are not clamping down a "self" employed barristers, I wonder why that might be.

I suspect IT contractors are not seen as real professionals in the British class structure

Taxes mostly and fairness towards people who are actually employed.

In the US you pay more to freelance in taxes than you do as an employee (because the employer pays some on your behalf) but you can have other deductions as a contractor. So I think fairness is not specifically a sufficient motivator. The UK can have a tax advantage for freelancing but these freelancers lose out on employment protections. Dunno..

US contractors don't seem to get anything - they seem to think getting a 20% premium over FTE is good.

In the UK you would normally expect 3x for a short 6 month contract.

Right but UK salaries are about 2-3x lower than US (at least for software engineers).. or at least they use to be.