Well the assumption was that there is no drag because the air density is so low. You can’t just say there’s no drag but still assume that you get lift. Your lift/drag ratio won’t go up infinitely just because you’re flying higher.
GP's assumption was travelling through space to avoid drag which doesn't necessarily imply generating lift in space.
My comment was not a support of that argument, but a clarification that simply being in space does not automatically mean no aerodynamic forces. I'm also not saying L/D increases, actually the opposite happens at higher speeds and altitudes.
