I am genuinely interested in understanding what motivates this reaction.
In general, it is procreation that makes humans think about the long term. The truth is, no matter what you do, you will be dead in a hundred years. Wanting to leave the world a better place for your children and grand-children is a much more powerful motivator than abstract philosophical principle.
I certainly think in terms of leaving the world better for all living things rather than for my children (although I guess they would benefit).
I personally feel shame that I am a part of the destruction of this world which in turn motivates me to want to make it better.
This is something that has grown as I have aged, I feel now that I'm older I can see things in the longer term and I can see how long it takes to make change and make it stick.
Parents who don't care whether the children are theirs biologically will have a greater tendency to raise children regardless of biological relationship. That means they are more likely to expend their finite resources on other people's children. That increases the likelihood that other lineages will prosper and expand, and decreases the likelihood that their own will.
Therefore we should expect that, with the passage of generations, the desire to have one's own biological progeny will spread and come to dominate the population.
That is, if such inclinations are heritable--or if a heritable desire to have one's own children appears in the population at some point.
Yeah, but this will only happen over the course of millions of years... not in 2050... Not to mention this is already the dominant desire...
I also think there's a tendency to anchor on what "is". Just because things are natural doesn't make them implicitly "good". And how does one define quality in the first place?
Put another way, what is the distinction between natural and artificial? Are humans not part of nature? And will "nature" not be here long after we've destroyed ourselves, if in fact we do?
They can but they (mostly) do not. And the best way to have a beneficial impact on environment in the current situation would be "simply" to reduce its numbers. Unfortunately that's not so easy.
There's some evidence that the Amazon mix of fruiting tree and nut species were selected for by humans.
"The Supposedly Pristine, Untouched Amazon Rainforest Was Actually Shaped By Humans"
https://www.smithsonianmag.com/science-nature/pristine-untou...
Since some people us this as political grounds for eugenics and population control. Such as one child policies, like China used to have. I think the proper way need to view ourselves, is as "gardeners" and caretakers. What we destroy in one area, we should rebuild in another, or make better.
For example, we could make connected "green corridors" that span the entire country, through which animals can migrate and live in. We have disrupted the migration paths of some species with out cities. But nothing says that we can't make it better by providing routes for these animals around our cities and farms.