That's for the nuclear industry to figure out. But the fact that companies from different companies originating in entirely different countries suggest that it's a problem with the tech itself.

The hard truth many just don't want to admit is that there are some technologies that simply aren't practical, regardless of how objectively cool they might be. The truth is that the nuclear industry just has a very poor track record with being financially viable. It's only ever really been scaled through massive state-run enterprises that can operate unprofitably. Before solar and wind really took off, the case could be made that we should switch to fission, even if it is more expensive, due to climate concerns. But now that solar + batteries are massively cheaper than nuclear? It's ridiculous to spend state money building these giant white elephants when we could just slap up some more solar panels instead. We ain't running out of space to put them any time soon.