The world population is projected to reach 8.5 billion in 2030, and to increase further to 9.7 billion in 2050 and 11.2 billion by 2100. As with any type of projection, there is a degree of uncertainty surrounding these latest population projections. These figures are based on the medium projection variant, which assumes a decline of fertility for countries where large families are still prevalent, as well as a slight increase of fertility in several countries with fewer than two children per woman on average. Survival prospects are also projected to improve in all countries.
The quote you give says this is the medium estimate. We would have to know the low and high to know if your estimate is "safe".
This assumes that people can move to such locations. We live in a society where most "developed" nations will on one day happily accept and try to help refugees from terrible situations, and on another day will shoot those same refugees at the border and call them "invaders".
And then there's the simple issue of many such people in dire need of leaving their current home simply being unable to at all. Undertaking the travel necessary to attempt to reach a "more developed" nation would be a death sentence in and of itself for some (for varying reasons).
https://www.un.org/en/global-issues/population
"No science agrees with this"
Sources?
Using your wolves example, people can move to locations that are more developed and have the infrastructure for more food distribution. The main problem is that most people are so far removed from their food sources that they don't really think about whether there will be enough for their kids. You could have people starving to death, or something wolves dont have - global conflict.