Anyone think this is an additional factor in the Fermi paradox? i.e planets that are too small can’t support a strong atmosphere and life. Planets that are too big make space travel too uneconomical.
I've often considered an alien planet with an atmosphere so thick that one couldn't see the night sky. Would inhabitants of this world even be interested in space travel? How much longer would it take for them to discover space, or even effective navigation of their own sphere? Maybe these people just wouldn't be explorers.