I'm West-Flemish myself and still live here, but I also get my share of snarky remarks of blogging in English or reading stuff primary in English. If you have a website with some text in Dutch and you make a spelling mistake then you will certainly get (angry) mails about it. Or when you use an English word instead of a Dutch, for some that is another capital offence.
If that sounds ridiculous keep in mind we have people proverbial running after busses and filling complaints when the bus company dares to advertise something with English words in it.
Ans seeing how many Dutch related contests Flemish participants win, I have sometimes the feeling that we are better in Dutch than our neighbours in the Netherlands. So yeah the Dutch language is really important in this part of the world.
For some things I can see the benefits of being able to promote (or even force) the local language. I'm personally convinced that from a social POV it helps when your neighbour understands you and speaks the same languages.
But on the other hand in the global age we are living we shouldn't overestimate the importance of it. It sometimes depresses me if I see how much energy gets lost in those kind of discussions.