To chassidishe gateshead, you are right that for a yid to survive he needs to learn self-control.(especially in america today). Without it, it would not be difficult for him to find whatever inappropriate material he wants, they practically give it away on the street corners and supermarket check-out aisles!
And still,we see there is no chiyuv to “move to a holier place”; plenty of mainstream rabbonim live here. Im sure there is no halachic need for you to leave the netherlands.
But there is a huge difference between all these examples and the internet: the internet is under your direct control, while the street is completely out of your control.
The street is a test given to you by hashem, whether you want to be tested or not, so you gotta learn self control or you’re finished.
But the internet is a nisayon that can be avoided, just by installing a filter( for most ppl, i dont know the specific situation of IT people). A test that is in your control to avoid, the halachah is clear that u must avoid. (Sanhedrin, 107a.)