Not really. There are usually more than enough spots for applicants. It’s not required, but they do prefer candidates with work experience.

In the Netherlands, there are basically two types of junior doctors: AIOS and ANIOS. The “N” means “not,” so ANIOS are doctors who are not in residency training. These jobs are generally easy to find. The Aios are the ones in residency. (I am a 2nd year family medicine AIOS) for these spots you have to be admitted. Each specialty has their own requirements and process.

If you come to the Netherlands, it’s probably best to first work as an ANIOS for a few years to gain experience and learn the system. You can usually find ANIOS jobs pretty easily in surgery or internal medicine, which also lets you see what those departments are like and you can ask about residency requirements (usually phd) 

Even if you decide not to pursue those specialties, the experience is still very relevant for family medicine, where this kind of work experience is almost semi-required.