I'm inclined to welcome Kruger's entry into to the debate even when I disagree with his prescription.
There IS a 'neoliberal', 'globalist' perspective on population. It goes somewhat like this: The world is (or was up until 20 years ago) experiencing population growth at an unsustainable rate that if unchecked will rapidly lead (once again) to large-scale famines, death, and genocidal resource wars of existential necessity. In a world armed with nuclear weapons this is a recipe for catastrophe. Therefore world wide population control is an urgent necessity. But fortunately population is not hard for humans to control: access to birth control, education, urbanisation, elimination of poverty and expansion of middle class affluence are enough to not only halt uncontrolled growth but set it into reverse. This rather unexpected development (from a Malthusianism perspective) is something that we should all be grateful for as it brings prosperity into alignment with sustainability. Within this frame, our current job (as wealthy countries) is to help developing countries achieve a sustained upward trajectory of affluence, and to absorb the current excess population that already exists on the planet. At some point in the future it might, if everything goes well, be necessary to collectively worry about over-all declining world population and develop strategies to target a long term stable population and introduce measures to boost population in order to keep humanity stable. But there's no need to worry about that now as there is plenty of population in the world.
This has all been tacitly agreed to by elites, but is rarely fully articulated and the public has never been given a chance to vote on it. Kruger is essentially saying that it's not Britain's job to absorb excess population from the rest of the world: it's destabilising, costly, and being used as device to manipulate the domestic political environment.
(Unstated) What's more it's not necessary, developing countries are perfectly able to achieve prosperity without exporting their population, and once they've achieved it their own demographic crises will disappear. In fact allowing them to export their population very possibly makes them reluctant to implement the changes necessary for their own prosperity.
As I said, I disagree with Kruger. My opinion is more aligned with the neoliberal globalists. But it's not beyond the pale - it's a conversation that should be had and people do have a right to vote on it.