But way before that, approximately around the time we had both mastered fire and good enough communication skills neanderthals and other homo became the very top of the food chain and started massively altering this planet.
I think scientists in the relevant field call the current extinction period the 4th? One caused by humans.
Sustainable is a "loaded word/concept" of the imprecise language we call English... For who? How long? For self / others? Externalities?
If Mark Zuckerberg creates a robot army and closed loop food producing system and clone installation that keeps him / his descendents alive till the heat death of the universe on an island in Hawai while 99.999999999999999999% of humans and animals die (some other billionaires on new Zealand etc etc) one could argue it's sustainable for said people but not very sustainable for "humanity"
There is no better way. Better way requires a big man / woman / it in the sky / your shoulder who supposedly knows.
You, me and most people on this forum are just the lucky ones (at least top 40% and most likely average top 3% financially ) who can imagine more than we can achieve in life and hence get philosophical from time to time...
Anyway I see you read / quote a lot of books so yeah recommend you the Derek Sivers book "how to live", he's much better than almost everyone at destillation and has the bonus of not having to sell.
Anyway as a tip: You can use sources / references but proof of authority / reference to authority (doctor this,..) Doesn't really add unless it's about a highly practical field. Can just add a source link at the bottom if you wanna reference his words but ideally the idea can stand by itself.