The other poster is comparing wage growth, not gross salaries.
Which has exactly the same sort of problem. If a government reduces employer taxes and increases employee taxes, you have a magical free gross wage growth.
You can't make incomparable values comparable by reducing them to a ratio, except in special cases.
To meaningfully compare countries you need to either compare the gross wage costs per employee that a company actually faces or compare the net income of employees after all taxes. And correct for purchasing power of course.