Suddenly my Netflix was only showing English as language/subtitles option, and no more Dutch.
I contacted Netflix via chat, and 'Jeremy' asked me "are you using a proxy, because we see you coming from the US".
Hmmm. I use Hurricane Electric's IPv6 tunnel, and as netflix.com has AAAA addresses, it could be my Netflix was flowing through IPv6, and because of HE's location, it was considered to be coming from the US. And thus no more Dutch language.
I couldn't find how to disable IPv6 in Chrome, so I started Firefox and disabled IPv6 via about:config. And ... tada ... the Dutch language was back.
So tunneled IPv6 has it's disadvantages.