Whether something is economically viable or not depends on how much time you spend developing the technology. Many materials in common usage today were exotic when they were first invented. Then economies of scale kicked in and prices went down. The US simply failed to invest into this technology. That’s the reality. China also has a long track record doing state level investment without seeking any immediate profit. The high speed rail system is a good example. Western media kept talking about how it wasn’t profitable, and that didn’t stop China from continuing to build it. There’s been no end of articles like this. And all of them completely missed the point that HSR is a long term investment that drives economic growth across the country.

Similarly, building thorium reactors is not a short term profit target. It’s a long term investment into energy security. Molten salt reactors can be built anywhere because they don’t require a large body of water nearby for cooling. They are extremely safe, there is no problem with long term waste, and China has abundant thorium reserves. That makes solving the materials problem an attractive proposition.