They wanted to restrict access to coffeeshop (not sure about brothel) to only Netherlands citizens but this raises constitutional problems.
They initially thought they would be at the forefront of a wave of legalization across Europe, but as it failed to materialize, their uniqueness brought their own issues.
I do have hopes for France though. Macron has the same political sense as Hollande, who just made a show of gay marriage legalization to prevent talking about other issues. I think they are keeping weed legalization as the next smokescreen.
On prostitution, the French liberals are a bit more divided. A lot of people actually associate human trafficking and prostitution and feel that criminalizing clients could be a way to make it go away. I tend to think that legalization would actually make the fight against sex-slavery much easier but I understand why people are more cautious about this issue.
Also the far-left shared some fake stories (but not totally implausible scenario) under which legalization of prostitution could mean that unemployed women could be forced by unemployment office to accept prostitution jobs or lose their unemployment benefits. They used the outcry to justify that prostitution is not a job like every other one.
It is a complicated issue, muddied by emotional bias and over-simplified solutions.