About how he went bankrupt.

That's when fossil fuel use exploded, making it about 150 years it took for us to screw up our environment.

It'll take a gargantuan effort, but we can still help by decreasing fossil fuel use, but not with assholes like trump begging big oil for million to help him get reelected...then they can do whatever they want.

The willingness of the elite to destroy everything to get what they want.

To acquire more wealth, power, and resources.

So in one sense there was absolutely nothing sudden about what we have done to the planet.

The desire to destroy the planet and others for wealth and power has always been present.

If it were not fossil fuels it would have been something else.

back in the day that we lived in harmony with the environment.
Of course, now we're much more destructive.

numerous animals have gone extinct due to "natural causes", in other words due to changes that may have involved humans natural progression to apex predator.
It didn't destroy the planet.

sabre-toothed tiger and dinosaurs being killed.

Come on, we're not descendants of Fred Flintstone. Humans didn't exist when dinosaurs were around.

The sabre-toothed tiger went extinct 11,000 years ago. The Cretaceous–Paleogene extinction event, which caused the extinction of the dinosaurs, happened approximately 66 million years ago.

By way of contrast, Fred Flintstone arose 64 years ago.

Humans capable of using fire and stone tools have been around for at least a million year. Modern homo sapiens is thought to be approximately 300,000 years old.

And throughout that 300,000 years we have systematically changed our environment and hunted various animals -- from the wooly mammoth and the sabertooth tiger to the dodo bird -- into extinction, or destroyed their habitat as our populations slowly but steadily grew. The ruins of ancient civilizations can be found in every habitable continent, and many (if not most) collapsed due to overshoot of their environment, not to mention wars, that left them vulnerable to the stresses of climate change.

The last hundred years or so have supercharged our destructive timeline, but they haven't changed it. Humans are doing damage on a global scale now instead of a regional scale, but it's not new behavior. This is who we are and what we do, and the thin layer of abstract conceptualization that sits on our animal brain got us into this mess, but doesn't know how to get us out of it.

Is that we went from being primarily survival oriented where we used what we needed, to becoming consumers of resources, including willful and wanton destruction of life and land for the sole purpose of having more, status, and pleasure.
What makes these last hundred years so harmful is that as more people could afford more, the cycle became more destructive in that we didn't just consume more, we demanded even more.
Sadly I'll add that it is we, the American economy/consumer that bears the blame as our voracious consumption didn't just use so much more than most, but created that "Keeping up with the Jones" effect that
just made things exponentially worse.

No, that's not even remotely true. The history of humankind is filled with stories of people consuming resources for status and for pleasure, and it usually ends badly.

Hunter-gatherers were mostly survival oriented, in between wiping out the large mammal species on every continent they moved in to, but the advent of agriculture some 5,000 to 8,000 years ago (depending on the region) change all of that dramatically. So we've been engaging in resource overshoot for THOUSANDS of years, not just the last 100.

Petroleum-based industrialization has super-charged our population and globalized resource overshoot, and it's introduced a whole new layer of pollutants. But this is a difference of degree, not kind. We are doing what humans have done since the beginning of the current interglacial, we've just gotten better at it as the centuries rolled by.

In 1750, the dawn of the industrial age, there were 750 million people that lived mainly thru farming land. Manufacturing changed from mainly work done by hand to using machines reducing cost and fostering innovation. And of course the increase in energy usage.

There are now over 8 billion people (10x) that are each using (pick a number) maybe thousands of times more energy during their lifetimes. We also create thousands of times more waste.

But what I consider astounding was during COVID when there was a huge drop in energy usage worldwide, the CO2 numbers from Mauna Loa didn't drop. Tells me that we are getting CO2 from environmental sources, not just from us. Methane from sea beds? Tundra thawing? Not sure at this point if it's reversible...

BTW - world population
1804 - 1 billion
1927 - 2 billion
1960 - 3 billion
1975 - 4 billion
1987 - 5 billion
1999 - 6 billion
2011 - 7 billion
2023 - 8 billion

https://www.worldometers.info/world-population/world-population-by-year/

Very debatable premise.

Many species of large game were hunted to extinction in paleolithic times.
Mastodons for the most famous example.

The real issue is the exponential population growth.

Some research points to the hunting of megafauna.

https://doi.org/10.1029/2010GL043985

Well, that is in America, the rest of the world is a long ways back

It isn't sustainable --- this life we live.

Be happy you are so fortunate and comfortable but do what you can for degrowth and don't make any more babies and limit your impacts