Feels like they were exploiting an artifice and always derived more than e.g. 75% of their declared income from a single source. As an outsider I believe the NL have some amazing obligations on employers above a certain size regarding social policy mandates and so the employer side may well have been complicit in this, to avoid social imposts for larger enterprises.

(Bodies I work with in Amsterdam have mandated workers councils, bicycle levies, social employment obligations, education and training requirements which scale to size)

Interesting. I thought "B2B" was a thing only in Poland. As in - who in Western Europe would allow that? I wonder if their tax rate is likewise better vs employment contract. Cause that's how it is in Poland if you earn enough money.