If we were on a planet with significantly lower gravity, walking would be much more difficult. Notably, on flat ground we absolutely must have an upward component to our application of force with the surface - this is clearly seen in videos taken on the lunar surface during the Apollo missions. This baby on a hypothetical lower gravity world would find standing easier, yes, but not mobility. At least not once he's taken his first few trail steps.
If gravity were lower we would have evolved differently, walking would have adapted too. On the other hand babies probably wouldn't be able to walk either. Being mobile, defenseless, and not having "runaway!" as the default defense mechanism (like horses) is an evolutionary dead end.
Problem is we don't have any good data about which gravitational accelerations would be suitable for long term health. We have 1g as our baseline, and we know that months in 0g messes you up and longer is a bad idea. We don't know anything about the long-term effects of living in Mars or Lunar gravity though. It could be studied using von Braun stations, but nobody has done it.
I did enjoy the first season of the series, but then was turned off by some story arcs, but maybe I will give it a try again. Are the books more consistent?
That series strived for realism in that regard, and in using magnetic boots to work in zero gravity; which was admirable. That made the things that were not realistic stand out even more imo. The (unfortunately named) Epstein drive, a drive that consumes very little mass under constant acceleration allows for relativistic speeds in very little time (weeks). Their ships were flying from one side of the solar system to the other in weeks, but they couldn’t make interstellar flights? Also the effects of cosmic rays and hard radiation on reproduction makes the disaffected belter population seem impossible. That’s all fine of course, just inconsistent imo.
Shohreh Aghdashloo performance was a real treat though!
The Epstein drives are efficient, but not efficient enough to run for months at a time without stopping, and are thus unusable for interstellar travel. The books go into that when talking about Medina/Behemoth/Nauvoo... The whole reason it had a rotating drum was because the engines would only be active at the start and end of the journey.
Regarding reproduction, I'm willing to write that off to advanced medical technology doing DNA repair. Most of the plot wouldn't be that different with slower space drives, so I wasn't too bothered by that either.
But fwiw, it turns out it is possible to get that level of rocket performance, if ToughSF got their numbers right:
It wouldn't look the same and the power level would be higher than what all of civilization uses today, but the amount of fusion fuel isn't all that remarkable. The design uses helium-3, which could be collected in large quantity from Uranus and Neptune.
