Interestingly the people who say others should die to “fix” overpopulation change their minds when they’re up. We can solve overpopulation in other ways than letting people die.
Sustainability would become vastly more important than our current short term horizons.
There's one other way to "solve" overpopulation, and it's galactic conquest. Everything else we might do eventually devolves into nothing but shades of austerity and deprivation as we divide our planet up between more people.
That's not to say that technical progress won't mitigate that problem. And yet, as it mitigates it, we tend to just make more people...so it's not like we're manufacturing much more runway for ourselves as a species.
In any case, I can't recall there being an epidemic of people doing the thing you're saying they do all the time: are you thinking of any specific examples?