I agree that making our planet livable is certainly much more important and we are very bad at that. But I don't see that researching livability on Mars makes us less likely to succeed on Earth. On the contrary, researching Mars livability probably has some probability of producing breakthroughs that could help us overcome our problems here.

Imagine for a moment we all stop what we're doing, crack our knuckles, and then REALLY clean our planet up. Clear the oceans of plastics, the sky of co2, the lands of garbage, and our hearts of consumption.

And then humanity gets wiped out by a rogue meteor. A rogue blackhole. A really bad solar flare. An object comes to our solar system and knocks us off our orbit. Our home is wiped clean in nuclear fire. Take your pick.

We have all our eggs in earths basket. I love earth, lets get the hell out of here though.

The technology that would allow us to survive on Mars could probably allow us to build self contained underground habitats that could survive a meteor, solar flare or even being flung out into deep space. Only something that actually resurfaced the planet, or destroyed it completely would actually require us to leave.

The most likely cause of Earth’s total destruction is our Sun turning into a red giant in a few billion years.

Why does it have to be an either/or proposition? We can and should do multiple things at once.