IF this was the cause then it is all the more sad given the excellent visibility just a few km from the coast (as Backpacker reports, he was doing aerobatics in perfect IMC just a few km away), and also given the perfect flatness of the Dutch countryside. There's not even any terrain to hit.
Naturally we know almost nothing right now though, so it's entirely possible that another more unusual failure led to the accident. It will be very interesting to see the official report, and see if there's anything to be learnt.