We may or may not have hit the physical point of no return. It doesn't really matter, because we obviously hit the point of political no return a long time ago.

In too much of the world, nobody with any kind of power cares. (My own country included.) It's the prisoner's dilemma yet again: why should any of us who might care cooperate, when everyone else is cheating?

We hit that point a long, long time ago.

The situation isn't hopeless, I think, but this talk of "point of no return" doesn't work because it doesn't acknowledge the reality that, as ever, it's political and some people actively do not want to address it.