I understand what you both mean. Theoretically who would want pure national state (even if it's possible)? But most of European states are national states with few minorities so reality is something else comparing to what we may wish for.
Even bloody USA and Australia are trying to make "nation" and keep telling their citizens they should forget where they are coming from. This is not an ideal world...not at all...And you just made one more national "state"...Kosovo. So how is this different from what Serbs wanted for them selves? And also Serbs still want Kosovo in their borders together with Albanian population. Except under Milosevic Albanians had more rights in Serbia then many minorities have in Europe on this day...