While climate hasn't been "stable" as in "hasn't changed", it has remained in a very narrow band of t°, of which we are slipping out of it at a much faster rate than all your examples.

I'd argue it's quite clear we are on the way to an extinction class climate change, are you saying we are not? The hockey stick graph is pretty alarming to me.

Humans don't need to coordonate globally to slow down emissions. I'm sure you are aware of what motivated small groups of people can do.

I'm not talking changing laws or protesting, but sabotage and disobedience in general are very efficient and need little coordination.