Like, we’re destroying the one place we know is a sure bet on where we can prosper if we keep it healthy, but instead the world’s richest man is trying to expand to other planets while this one’s ability to sustain life is in jeopardy. IMO that makes us potentially a very stupid species compared to a species that doesn’t really care about meeting other aliens because they value the life on their own planet far more than we do.
I don’t think that’s accurate to say at all. If anything, our current climate crisis points out that there are potentially multiple ways that we are nearing population limits. Sure, we could move to cleaner energy and prevent population growth from impacting the planet, but we aren’t doing that, not fast enough.
We keep using more and more land for farming, and that often means destroying existing habitats, which has a real ecological cost. We could prevent the destruction of more habitats with advances in vertical farming, but generally speaking, those methods require more energy and have larger carbon footprints.
And ultimately, even if agricultural techniques keep up, there are simply other limits. For instance, you can’t just generate more energy forever. Even with a mastery of fusion power, making free energy out of water, at some point the generation and use of energy heats the planet too much directly. You don’t reach that point until your generating energy for trillions of people, but that’s a hard limit, boiling the planet is not an option.