I’m in two minds (which is unusual for me).
My first reaction, having read the first bit of the article was “Why not?”. If UK citizens want, for some unfathomable reason, to retain “EU Citizenship” then that’s up to them. (Although “EU Citizenship” is not a concept I accept. The EU, not being a nation on its own, cannot really have citizens. In the same way that only independent nations can issue passports, citizenship can only be granted by independent nations. However, a trifle pedantic as far as this question goes). So long as the measure does not confer any special rights to citizens from other EU nations as far as the UK is concerned, of course. And there’s the danger; the EU does now’t for now’t and they will surely be looking at some reciprocal measure from the UK.
But then I read this within the article:
“…and young people looking to flee an increasingly insular UK”
That description could not be further from the truth. In seeking independence from the EU the UK is actually reaching out to the rest of the world, looking to rid itself of an increasingly inward looking, protectionist, interventionist and centralised EU bureaucracy. The Euromaniacs still don’t seem to recognise those shortcomings.