Edit: okay, that turned into a bit of a ramble :)

TLDR: at some point, we have to come to terms with the fact that Earth has not got infinite space or an infinity of resources. The sooner we start acting on that knowledge, the better for everyone.

Why would we ever want even more people when we struggle to properly serve the current population? And we've struggled for many years. Immigration is critically important, not for population, but for diversity. Monoculture in all forms is weakness.

I have no problem with urban lifestyles and actually miss some aspects of it. But we are rapidly losing our ability to support alternative lifestyles. Small cities that once thrived now struggle. Towns and villages are becoming less viable. Yet campgrounds are collapsing under the weight of demand.

I've lived my whole life, 67 years, in Saskatchewan. Our population grew by 10-20 percent during the time that Canada's population grew by 50 percent or more. In the 1960s an 70s it was rare to not be able to find openings at any campground on the spur of the moment. That started changing in the 80s and 90s when popular places would fill up on long weekends. By 2000, we had to start making reservations. Today, all but the most out of the way campgrounds require weeks or even months of planning and, often, all but the earliest of birds are shut completely out.

It may seem strange to focus on campgrounds, but I think that this demand is at least partly driven by the loss of non-urban choices in lifestyle. To a first approximation, it was never the villagers and farmers and ranchers who were driving campground demand, but the residents of cities. If everything is to be urbanised, what is left for those for who would choose something different? If we cannot serve the variety of human needs or even such a simple and basic human need to occasionally escape, what hope is there for anything else?

At some point, whether in 50 years or 500, we are going to have to find ways to deal with steady or even falling populations. Nothing about this little rock is infinite. The sooner we recognize that and start building our economies, societies, and institutions accordingly, the less aggressively we need to act. And the less aggressively we need to act, the easier it will be on people, businesses, and nature.