I'm not talking just about UK. I don't care where people are from or where they go. It's literally a numbers game. If, in order to survive we're working off the basis that we need more people in every generation in order to afford to pay for the previous one then we're fucked. It CANNOT happen forever, but we'll just blindly carry on working off that saying to ourselves 'it won't be us that suffers, so who cares'. It may be your great, great, great, great grandchildren, but who gives a fuck about them.
Improvements in working peoples pay and conditions almost always come at a time after there has been some disaster resulting in significant population loss - wars, pandemics etc. - because their overall value becomes higher purely because there is less supply. Places with high populations have low wages and poor conditions because workers are seen as dispensable as there is a plentiful supply to replace.
And the problems goes way beyond humans. So many things are getting worse because of the huge human population explosion post-industrial revolution. Climate and weather is becoming more extreme. We have huge problems with flooding because of us building on it. Air, land and water are polluted. We're currently in a period of mass extinction, and much of the reasons for that can be laid at humanity's door as we destroy or contaminate habitats so animals have fewer places to live, breed and feed.
Diseases like cancer are through the roof. Living in closer contact means diseases can spread like wildfire, and as current anti-biotics become ineffective (for those parts of the world lucky enough to have ready access to them) the risk of an untreatable disease/infection rises. The pandemic, in reality, was quite mild compared to previous ones, such as Spanish Flu or previous plagues. Imagine a quarter of the population being wiped out now in the space of a few years? 2BN people! And chances are given how quickly and easily we can travel the world these days, as well as living in closer proximity the conditions would be ripe for it to be way higher.
Relying on population growth can ONLY end in eventual disaster, and rather than being selfish and working on the (fair) assumption that it probably won't be us that bears the brunt of the suffering, we need to accept responsibility and look at different ways we can survive on this earth sustainably without taking over and destroying the entire thing.
But, yeah, that's not going to make someone put an X in the little box is it.