Nuclear fission is a compact, high powered energy source. It is a practical and cost effective energy source for energy generation on submarines, warships and spaceships. In 2019 however, it is not any longer worth advocating as a source of power for civilization on Earth (or any of the Inner Planets in this Solar System) given the last decade of cost reductions in solar and wind power coupled with low cost battery development. This is well understood by the market, politicians and the general public, even if the nuclear lobby hasn't come to terms with this reality. Even if plants could be built 6 times cheaper as this article suggests - which is both unlikely (given the track record of the industry) and unwise for ratepayers (given the history of cost offloading on the public) nuclear is unlikely to compete with renewables for the foreseeable future.

The entire article is written as a polemic (which is fine) but it argues against various straw-men and obfuscates the problems with nuclear power today. Some examples include:

Caiming it is "fantasy" that renewables alone can power the transition to a carbon free economy. Their argument? "Wind and solar power are becoming cheaper, but they are not available around the clock, rain or shine, and batteries that could power entire cities for days or weeks". This confused statement doesn't actually address the best argument of renewable energy advocates - that renewables could power entire cities if given sufficient generation and storage capacity. An argument indicating the limits of renewable power generation and battery production is required, but the article makes no such argument because it would not hold water. Also, if there is no daylight for weeks (nuclear winter?) there may be bigger problems to address than carbon emissions.

Also, the article does itself no favors by comparing itself to coal. This is a dying energy source (especially in the US) - the fact that nuclear is better than coal impresses no one.

Another trick used is sentences like this "By contrast, in 60 years of nuclear power, only three accidents have raised public alarm". It is quite likely that most nuclear incidents raised no alarm because they weren't reported. The public incidents cited were simply too large to go unnoticed. Does anybody believe the only lethal accident or cancer causing radioactive lease in the Soviet Union was Chernobyl?

Another crazy claim is "Nuclear waste is compact — America’s total from 60 years would fit in a Walmart — and is safely stored in concrete casks and pools, becoming less radioactive over time.". This is simply not correct as written. If America's waste was well managed it might fit into a Walmart (I didn't do the math), but it is isn't. It is a poorly manged mess, even leaking into groundwater like at Hanford. Hanford's cleanup wouldn't cost $113+ billion to clean up if nuclear waste sat in well organized casks in a Walmart sized warehouse. And Hanford is is just one (large) site (https://en.wikipedia.org/wiki/Hanford_Site).

Finally, the article deals with nuclear proliferation with this paragraph:
"Nuclear power plants cannot explode like nuclear bombs, and they have not contributed to weapons proliferation, thanks to robust international controls: 24 countries have nuclear power but not weapons, while Israel and North Korea have nuclear weapons but not power."
Again, no one is claiming that that nuclear plants explode like nuclear bombs (straw man). However, claiming they have no contributed to weapons proliferation requires a special reading of the paragraph where proliferation counts only as documented cases of nuclear material migrating across borders to be incorporated in nuclear weapons. The fact that nuclear plants produce material for nuclear weapons (whether it crosses a border or not) means nuclear power can (and does) contribute to weapon development. Israel may not have nuclear power plants, but it has "research" nuclear plants (Dimona) that probably produced the material for its bombs.

It's unclear to me if this is a good faith opinion piece.