I get the sense that you are a tad cynical.
If I may play devil's advocate for a moment, aliens are, if nothing else, alien, so what makes sense to them might well seem bizarrely nosensical to us. It's a bit cliché but perhaps they (if we assume that they exist, for the sake of argument) just don't feel that the majority of us are 'ready'. Who knows.
The planet is not even remotely "on its knees" with climate change. Maybe it will be in future but, as things currently stand, we're coping fine. And humanity has so far proven its ability to
not turn the planet into a nuclear wasteland. This is all quite positive, to my mind.
This is pointless speculation but perhaps that's just no their way. They;d rather we do learn to do ourselves or, more realistically, to learn to cope well with change ourselves.