No it doesn't. Mars today is likely less habitable than post-asteroid earth. Also, Asteroids can hit Mars with the same likelihood - but with less protection from an existing dense atmosphere.

[1] https://www.technologyreview.com/s/508906/mars-astronauts-li...

The probability of a civilization-ending asteroid impact on Earth and Mars at approximately the same time is a lot less than the probability of a civilization-ending asteroid impact just on Earth.

Wouldn't it be cheaper to defend against an asteroid impact? We only need detect and deflect in time.