I will admit that I know very little on either Phillip's or Attenborough's stances on population control, besides this video where Attenborough's speech on the issue, and that English people for whom they are closer to home would very likely know more on the answer to the question of each individual's stances on population control may be.

I would say that for someone who may be interested in investigating their interests in the area by examining the public records for additional instances that they are pushing for normalization of acceptance of mass deaths via moving the goalposts by looking for records prior to that 12 year old video and after it as well to see whether or not their rhetoric has significantly shifted since then in addition to whether or not Malthus is used in more than a singular throwaway sentence on what future aught to be avoided.

Which brings me to a secondary point that Attenborough had, to my recollection, only mentioned Malthus once in sections you selected for - what is a rather long speech of an hour and some change - rather briefly before moving on towards highlighting his own proposals to avoid such a wretched future in his rather bland proposition of women empowerment, sexual and family planning education, and so forth.

And finally with regards to your comments with how this is all in the name of the creation of a 'Fortress Europe' I would assert that such measures aren't necessary in the first place as the European states are already quite xenophobically racist without additional input from the island of blockheads - not withstanding the fact that the American war on brown people terror had been supercharging the xenophobia of the European states since 2001 - to the point that fortress Europe has already existed since the destruction of the many west Asian and north African countries by their and America's hands culminated into the refugee crisis of 2015 which as we are both aware tore off the mask of European compassion and charity.

If we bring this back into relevance with England, in regards to the video, one would simply point towards the 2020 Brexit referendum as the culmination of the xenophobic reaction of the islanders towards the nasty foreigners crossing the Channel to steal their jobs - like the Poles - to come to the conclusion that even a fortress England exists as well.

Additionally I have to stress the point that western states media predispose their respective peoples to be apathetic towards the deaths of others with their yellow journalism that the death of one domestic European or white American is equally worth reporting to the death of thousands in, well, just name a non-european country. One can simply see how American media treats hurricanes that cause a handful of deaths in the southern states as tragedies that deserve to be discussed for weeks to months whereas the deaths of hundreds from the same hurricanes passing over Caribbean or Latin American countries barely get a passing mention.

I bring up already-existing fortresses Europe and Terf Island in addition to the paragraph on western media as examples that the English bourgeoisie don't need to persuade their own upper crust to be prepared to accept the deaths of millions of foreigners from climate change when their own broader society is already propagandized to do so at any particular catastrophic event.