Yeah but they aren't. And they won't.

If there was collusion going on, compensation never would have skyrocketed over the past decade.

There have been multiple times in the past decade that FAANG colluded to decrease wages.

I can only think of one, and it was an anti-poaching agreement from 2005 that the involved companies paid compensation for later. I haven’t seen any reason to believe that is still happening.

I wonder what kind of collusion Europe is up to, with salaries at 50%-20% of those available in the US.

Productivity is generally lower.

2x-5x? Color me skeptical. Depending on what's behind that statement, it could actually be a bit insulting. I've been to US tech conferences; US developers aren't doing anything differently than the Northern European ones. Many times, I've heard discussions of at those conferences of processes that are more broken than the ones I wrestle with.

It's a combination of corruption, collusion, widespread inefficiencies that limits high salaries at the margins (meaning that the marginal company available to each employee is never desperate), very high pre-payroll hidden taxation. Also, importantly I think, a lack of competition between multiple globally dominant tech companies with huge profits per employee and a very obvious pathway to monetizing each additional employee's labor.

So, complex answer. But I'd stake money that collusion, often silently government-sanctioned, is significantly more common than in the US.

An example of this is very common in Norway, where practically all education is state-funded and the number of students for each profession is directly decided by the state. Private-sector interest groups have almost direct control over some of these processes, disguised as a public debate in the newspapers leading up to quota decisions. This leads to an almost planned economy of the availability of professionals.

Comp is still 2x less than it should be