The basic tenant of socialism is first
to abolish all private property.
If the Netherlands will allow people to own their homes, they simply cannot be socialist. That would be like someone who doesn't believe in Jesus saying that they are a Christian. It just doesn't work that way.
Or not. In the modern day, governments that have a mixed economy (such as the UK) practice "interventionism". It's also called a mixed economy for a reason. A European country that taxes you heavily to pay for lousy health care simply is not socialist.
Even in business classes, the first things you learn are the differences between Socialism and Capitalism, why pure Socialism doesn't work, and why pure Capitalism exploits the poor and old. By your definition, any government that tries to help the poor, old, and sick are socialists.
It took a while for you to find me; I was hiding in the lime tree.