They were "too far" because the EU has demonstrated over 20 years a political inability and unwillingness to make them work. This is not a theoretical argument.

Regarding Schengen, for instance, I have been taking night trains between Spain and Frence for nearly 7 years now and I have always had my passport checked at the French border by French customs officials. As far as I'm concerned, France has always been in violation of the spirit of it.

Economics is politics by other means