Everything needed to go from Q > 1 to actual electric power is nonexistant, not even being worked on, and far beyond the resources of these companies. Nobody knows how to produce the tritium needed to operate, or to extract it at ppb concentration if they did. Nobody knows how to build structural elements that will not fall apart after a few months' neutron blast. It has been decades since either was seriously looked at, with no promising ideas forthcoming.
That hasn't mattered much thus far because Q is so far off, and investors pour money in regardless.
That hasn't mattered much thus far because Q is so far off, and investors pour money in regardless.