And realize this also depends on how much the competition costs. If renewables and storage continue to get cheaper, fusion that "works" in an economic sense could transition back to "doesn't work".
It's the fate of most technologies to fail this way, so it shouldn't be surprising (or a source of dishonor) if the same thing happens to fusion. That doesn't mean money spent developing fusion is necessarily wasted; the size of the energy market -- a quadrillion dollars or so over the 21st century -- justifies longshot investments.
Bear in mind that Helion's reactor is 50MW, about the size of three large wind turbines. If it works they'll be mass-producing them in factories and shipping them by rail, and they'll have a declining cost curve just like anything else.
It's the fate of most technologies to fail this way, so it shouldn't be surprising (or a source of dishonor) if the same thing happens to fusion. That doesn't mean money spent developing fusion is necessarily wasted; the size of the energy market -- a quadrillion dollars or so over the 21st century -- justifies longshot investments.