That's fair but the strong Islam presence has lots of people upset to the point where I would say the Dutch (as a group, of people without religion or subscribing to some religion) are now less tolerant of (other) religion(s) than they were 20 years ago. This is a factor in the right wing extremist presence who use this to drive a wedge between people who otherwise probably would not care that much, it is clearly positioned as 'Islam against the rest'. Most notable for this is Geert Wilders, who is a complete asshole but there are others as well.

Gelderland (where my family is from) is definitely more religious than say Amsterdam, but far less than the South of Limburg or the 'Bible Belt'. At the same time, those are all various offshoots of Christianity, whereas if you were to look at Islam you will find the opposite, it is strongly represented in the big cities, where there is hardly any Christian offshoots left (and if they are they are dying).

Churches are disappearing, Mosques are rising up everywhere, and I'm not sure if the longer term will find NL with a more tolerant version of itself or if it will regress at some point.