Until not that long ago we had similar 'non-enforcement in practice' for small amounts of XTC pills and under a gram of cocaine.
In general Dutch policy is/was about allowing and educating towards responsible use which means that, especially in big cities and certain big parties, there is a subculture where hard-drug use is condoned and to some degree par for the course.
Culturally minimal responsible use (a tablet once or twice a year, a line of cocaine to extend a party once) is considered as 'your choice and I'll try not to look down on you for it,' but any form of dependence is heavily frowned upon and discouraged.
In general it's part of a broader theme of giving you the freedom to make your own mistakes as long as they don't negatively impact others, which comes with a lot of implicit cultural experience in how to let people experiment and come to their own terms with these drugs without losing them to the drug.
In practice it tends to take the form of most people 'going through a phase' and growing out of it, a small amount of people becoming high-functioning long-term addicts and an even smaller percentage of in-the-gutter destroy-your-life type addicts.