I'm pretty sure that was what NASA was going to do all the way back in the 70s before their funding got slashed. It was a novel idea but not a novel idea that SpaceX was particularly responsible for, just one they threw capital at because the government stopped caring after the space race.
Nuclear power research, by contrast, never really suffered from a lack of available funds. They were throwing money at mini reactors back in the 90s, saying all the same stuff about how mass production would bring down the price.
So, while in theory it may have had the money, in practice it did not.
It's not entirely bad though, I'm sure lots of those folks are doing good and important stuff. But I don't think the balance between employment and building things is quite right. At least to my tastes.
I think small modular reactors are the way out of the similar cycle we've got for nuclear reactors. And I think that building a small number of large ones is going to be a lot better if we're also building a large number of small ones and learning.
It's like not building a y houses for 30 years and then building a massive skyscraper. If that's all we do then we'll only ever have one way of building a skyscraper because there's no room to experiment on other construction materials and techniques.