If you make it much cheaper, then everything else flows from that. You no longer have to spend years engineering everything at the cutting edge of your mass budget. You can use off the shelf parts, you can have redundancy.
The gains will come when these flights become commonplace.
That was done and the results were published a few months ago, but the study did not have any relationship with SpaceX.
The results were rather pessimistic for the long-term missions on Moon or Mars.
In my opinion, even if it is possible that humans might support a somewhat lower gravity than mice, the conclusion is that for interplanetary travel humans must use only spaceships that create artificial gravity by rotation.
The results of the study were that mice require a gravity of at least 2/3 of that of Earth to stay in perfect health and of at least 1/3 of that of Earth to avoid extremely severe health damage.
This means that even on Mars the gravity is not sufficient for long-term human life. In an underground Mars base, one could make a part with increased gravity by rotation, where the crew should spend most of the time, but that would increase a lot the complexity of building and maintaining such a base.
Unless someone invents the Epstein drive we aren’t going to have astronauts experiencing acceleration for months rather than minutes of the trip. And the more constant the acceleration the shorter the trip anyway.
The origin of SpaceX with Michael D. Griffin and Pete Worden really make it clear though.
How much time is needed to do the required research? Like, how long it would take to learn how to create an artificial biosphere on a small scale, so you can have a farm on the Moon or Mars? 10 years? 20 years? Maybe 50 years? Isn't now is the good time to start the research?