I have never meant anyone who's concerned about Earth's ability to perpetuate its ecosystems in 800 million years. People are concerned about its ability to (comfortably) support human life 20, 200, or (maybe) 2000 years from now.
It seems as if you're trying to imply that industrial humanity hasn't had a uniquely destructive impact on the natural environment over the past two centuries.
Everyone is obsessed with these short time scales. But I’ve yet to see someone propose a viable alternative to human civilization on a 800M year timescale.
Yes, I do believe humans are bringing about the end of the Holocene. But I’m fairly forgiving of the human race on multiple grounds:
1 - life on earth needs a ticket out or it dies in 800M years no matter what. That ticket requires escaping orbit and establishing itself on another rock. I have no reason to believe that any species that evolves to successfully do that would fair better than humanity. It doesn’t matter how far in the future this event is, it’s a critical path for at least one species to follow if life on earth is to end in any way other than complete extinction. If it has to happen - it has to happen. And so far, I haven’t seen many great arguments for viable alternative timelines of human (or non-human) progress that avoid complete extinction in 800M years.
2 - No other species on earth, that I know of, self identifies that it is past the ecosystem’s carrying capacity and attempts to self correct. For example, white tail deer in the Midwest will gladly keep having babies and eat all their food supply. The plants all die. Then the deer all starve. Then the wolves and coyotes all starve. And then the cycle repeats. The deer don’t call international food symposiums to talk about the sustainability of harvesting their food stock. This is a uniquely human trait. Humans are held to a different standard because we know better - which in and of itself is amazing and gives me significant hope.
TL;DR: there isn’t another species that I’d bet on to do a better job at saving all life on earth than what humans are already doing. Yes we have work to do, of course we have work to do, because we are literally life on earth’s only (risk adjusted) chance. If you’re not trying to sustainably save life on earth, what are you advocating for?
I don't feel completely safe in ruling out cephalopods in that regard. That said, life on dry land would seem to be a precursor to scientific advancement such as chemistry.
What?
Most of that is fairly bleak.
There is this nonsense idea that the earth would be fine if humans didn’t come along. It wouldn’t. This planet is in its death throes. Life has delicately established itself in a habitable zone that is coming to an end. The carbon cycle has a good 800M years left before photosynthesis starts grinding to a halt. That might seem like a long time, but life’s been here for a good 4B years - we are 75% through life on earth. It’s taken evolution 4B years to print its first ticket off this rock: humans. That it’ll print another in 800M years is a poor bet.
The idea of saving life on this planet by curbing human progress is a fools errand. You save life on this planet by bringing it with you when you leave this rock.