It doesn't take a xenophobe to be annoyed at unhappy pops because they chose to live on an arid world while their genetics favors oceans. And it's not like the other planets are full either.
Obviously it does. People live in different climates than where their ancestors lived all the time. Nobody gets pissed off when a person born in the himalayas moves to the netherlands. Sure, the person born in the himalayas may have a natural advantage to living in really tall mountains, but very few people are interested in forcing them to stay there. This is not the only example. Africans with darker skin have a natural advantage in very sunny climates and a natural disadvantage in arctic climates. The african that moves to alaska has to find a better source of vitamin D, because the sun isn't doing enough. Nobody tries to prevent Africans from living in alaska. Point is, people groups over time through natural selection have developed specific ecological adaptations that predisposition them to healthier living in certain locales. It doesn't mean that they will choose to live in those locales if given the choice to go elsewhere.
But this is all digression. My original post was about how only xenophobes would prioritize the growth of specific species over others, or prevent a particular species from reproducing entirely. If you want highly specialized species in each environment, the cost is slower growth. That's just the cost of segregation, because you are actively limiting the choices of your pops on where they want to live. Just like in real life, people can make choices and they don't always line up with what we might consider rational.
But it would be cool to see population control restrictions expanded. Like if you're authoritarian, you can limit the growth of slaves or workers, etc. That'd be pretty cool.