The supposed “uninhabitability or uninhabitedness of other planets in the Solar System” is shit science.
It’s a hypothesis pretending to be a fact! It’s based only in extrapolating the principles of earthly life, disregarding that other life may thrive under very different conditions.
Metaphysics can help here. We live on a planet made of water and earth, and we ourselves are made of water and earth. It only makes sense for rocky Mercury to be home to rock-like beïngs. The Bhagavad Gita states that life exists on every planet, and that the Sun is home to beïngs made of fire.