Hi Dr. Harrison -
It is important to not lump all billionaires together - we would not lump all scientists in one bucket either. Bezos is as different from Musk as Jennifer Doudna is from Einstein.
I wish things were different, but the US government does not have the will to do anything long term except maintain an army. The main reason is that the public generally doses not understand the "need" for space and has little interest in it. The public likes stunts; once the stunt is done, they lose interest - and so does funding.
Also, space is about more than science and understanding our place in the cosmos. A lot of people (myself included) feel that we should learn to settle these hard to reach and dangerous places - that we should tame them and create a richer and more interesting habitable landscape across the solar system. Taming the solar system to make it livable it a far higher challenge than climbing Mt Everest or putting a flag on the Moon. And if we can do it, life will be amazing.
Some people are not interested in doing that. People's values vary. Some people value are (I do not). Some like sports (I do not - feel the the $50B spent on the Olympics is a waste, and see no value in sports stadiums). But luckily we are each free to pursue our own dreams. SpaceX is pursuing their founder's dream; and it is not about a legacy or ego: it is a dream - a dream as valid as any other.
And it will take a billionaire to do it - a billionaire who is brilliant and young enough to go the distance. Either that, or a totalitarian government that makes it a long term goal. But in the US it will not happen.
Perhaps your sentiment is, at its core, a lament that the public is not more interested in space. That lament, I share.