He has been identified!
News article in Dutch:
Aangespoelde zeiler na 25 jaar geïdentificeerd als Zweedse man | NU - Het laatste nieuws het eerst op NU.nl
He was a 59 year old sailer named Hans from Sundsvall, Sweden.
This summer the police spread a message through Swedish media, because the watch was made for the Swedish market, and also the pants indicated a Swedish origin.
A woman recognized her uncle in the story and a DNA match was made with his children.
The mans daughters are happy that they no longer live in uncertainty about what happened to their father, why he didn't react to their reaching out for contact.
Because of circumstances they never reported him missing.