https://news.ycombinator.com/item?id=20782346
(Needless to say, I don't have a high opinion of current fusion start ups.)
And fission already had the financial fiasco of the first nuclear build out in the US.
Solar could have been predicted to get really cheap, if one had heroically projected its experience curve into the future. A lot of people chickened out doing that, even Greenpeace.