Because it's technical and an advanced form of technology which appeals to tech people and where normal people have an "irrational" fear of it. And also IT and conversely HN is full of people who have trouble fitting in and pride themselves on being rational, and have made it a career and lifestyle of going the other way as everyone else.

Which is fine, except putting hopes into a technology that has failed repeatedly for 60 years is in itself irrational.

HN would do itself a favor if it learned the lessons of "worse is better" and applied it to, well, almost anything. In this case, a moonshot to advance nuclear globally might bring realistic results in 10-15 years. By that time the world will already be decarbonized by renewables as it's already happening. At best nuclear might be that last missing piece to get to 100%, but even this I would no longer bet on. There is already insane growth in undeveloped countries which will push demand even further. Renewables are ridiculously cheap.