There is Arthur C. Clarke's essay "Hazards of Prophecy: The Failure of Imagination"
Another aphorism: "When in doubt, predict that the present trend will continue." In the case of fusion, the trend is achievement of ever increasing capability. But distinguished scientists of all ages sometimes fall into the other trap of predicting that something won't happen because for millennia it hasn't happened yet.
Some prognosticators failed. So, what else is new? Oh, repeatable advances in plasma physics as the OP illustrates. Thank you, the ever valuable Judi Lynn.
Deuterium-Tritium fusion is only one of several reactions available. D-D draws from 0.016% of water, but there is a lot of water. Tritium can be bred from lithium nuclear reactions.
Certainly the scale of nuclear fission energy production can be scaled up, but itself faces severe challenges, among which is that scaling up is not as easy as paper exercises seem to show. They tend to require massive capital investments. Where they are done cheaply, they tend to have severely damaging failures. To counter that there are efforts to makes small reactors which are also promised via announcements of breakthroughs with a frequency not unlike announcement of fusion breakthroughs. Massive scale up of nuclear fission energy production would also mean scale up of number and severity of failures. Nuclear waste is the ultimate NIMBY. Even transporting it is a big deal. Last but not finally or least, scaled up nuclear fission power would be run by the same ilk of corporate greed that saddled us with excess atmospheric carbon in the first place.
There are no easy solutions to the dilemma. Societal issues have to be addressed with technological solutions and societal solutions can enable technological deployment. Constant railing against all partial solutions except one favourite is I think a variation on the all-or-nothing group of fallacies.
No partial solution is perfect but there does not have to be one perfect solution. The integrated totality of partial solutions is greater than sum of each individually. If we are serious about the competition of ideas we have to move forward on multiple fronts.
No single solution can be chosen (by who?) to satisfy all societal constraints and balances. Who are we to decide for humanity what the balance of million-year risks versus instant risks versus 30-year risks etc is? Technocrats? Facebook polls? In the absence of a world government (dubious desirability) that functions well (could never happen faster than mature nuclear fusion power), ... in that absence we must try and we must do what we can. Fusion is obviously not a short term solution and we are in desperate need of a short term solution. But neither is massively deployed fission with the current state of that technology and public concerns (which have some legitimacy and must be considered).
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