We should focus on making the Holodeck, not rockets.
Once reliability is proven one could even start thinking about nuclear powered rockets and get those CO2 emissions to zero. I'm sure it is on Elon Musk's mind and Mueller has even mentioned looking into nuclear rockets. Solar system travel could really use nuclear rockets to get reasonable travel travel times.
As for the very HN-ish "why don't you just go make XYZ?" retort, obviously it's because, like most of us (and unlike Elon Musk), I don't have the necessary truckloads of $100 bills necessary to make that happen. I'll get back to you after my windfall from selling PayPal...
Technology does not just progress by magic or money. People must do the hard work. The world is awash in capital at this moment with negative interest rates in some places. Physical resources (or money) is not the limitation for getting most new things done in the world at the moment. It is the complicated process of getting people working together, taking a million false steps, and not giving up before finally figuring out how to reach a goal.
Curiously, what was the 28K spent on? Maybe 12K for rent, tops for 1995. He even lived in the office. Someone chime in?
Since he's focusing on that, why don't you go ahead and focus on making the holodeck. Thanks!