My point in "most people" isn't necessarily even that the presumed statistic is correct, but that litigating the question of what is meant by "saving the planet" is a boring and to me frankly stupid discussion. It doesn't buy you much.

I conceded that there are people who do advocate for eliminating of humans entirely. Derrick Jensen, Lierre Keith, Stephanie McMillan, and Jack Forbes, and their Deep Green Resistance advocate for this: https://en.wikipedia.org/wiki/Deep_Green_Resistance It's not a terribly popular view. It is an extant one.

Again: I'm acknowledging the view exists.

On the question of predicting outcomes -- that's something I've been looking at, and I'm starting to conclude that there are models which are more effective than others, though they're not perfectly accurate. Most take an ecological approach, and consider physical effects or carrying capacity. Looking at past predictions, and noting both which are or aren't accurate AND WHY is hugely instructive. What I notice is that a particular viewpoint (generally anti-Malthusian) seems to glory over missed specific benchmark elements (dates, quantities, etc.), without looking at the underlying causal bases.

Using the inability to predict long-term outcomes as the justification for shifting the basis of what you're claiming to be impossible predictions from the ecosystem as a whole to humans alone doesn't, on brief reflection, seem to offer much. "We can't predict accurately, so let's predict inaccurately on topic B rather than topic A."

I'm not sold.

The question of how to ramp down human population * consumption to a sustainable level is a very hard one. I'll point back to the diagram of terrestrial biomass I posted higher up this thread (https://news.ycombinator.com/item?id=12453058). We're looking at a situation in which:

1. Humans and their livestock represent about 5x the long-term sustainable terrestrial vertebrate biomass of the planet.

2. Humans alone represent nearly 2x the long-term TVB.

3. We achieve this through the exploitation of massive amounts of stored energy, consumed at the rate of about 5 million years of original accumulation per single current year of use.

4. The environmental impacts of that rate of use itself pose considerable environmental threats.

5. There are numerous other binding ecological constraints we're facing either currently or in the near future.

"Helping humanity itself" is going to involve something thinning the herd considerably. I've got reasons for suspecting endogenous mechansisms are messy, though exogenous ones also seem that way.

Either way, humans now live in a period where our most pressing and clearly identifiable existential threat is ourselves, through sheer mass of numbers.

There is a difference between acknowledging (and understanding, and appreciating) the problem, and in coming up with a solution to it. But the first is a prerequisite for the second.

The author of the chart I showed above has a "ladder of awareness" which I find instructive. His view generally is rather Zen. I've not fully bought it, but it strikes me as strongly considered. Paul Chefurka:

http://paulchefurka.ca/LadderOfAwareness.html

(see more at http://paulchefurka.ca)