I have a partially distorted view, because those Dutch I do know are fluent in English, so I don't have such a quite accurate picture. I would say my younger cousins and friends happen to speak it with a better accent than my older cousins, however my older cousins are proficient in more languages than the younger generations.
If such is the case, I'm curious as to the decline in English proficiency as well. Though it may be a stretch to say that two Dutch men not knowing the word cumpulsory means the entire country's skills are dropping, since of course among the Dutch you've always had those who are very skilled in other languages and those that just aren't, but if you've had many other similar experiences then that would give serious weight to the issue.