The economic projections were probably always too optimistic but nuclear power also became politically much more difficult. "Sitting US president has to personally show up at the site of an ongoing nuclear accident and it's not even his first ongoing nuclear accident rodeo" is not, as we now say, a great look.
I'm sure that's true, but am noting that in Illinois the competitive disadvantage nuclear has against gas has the state actively subsidizing some unprofitable nuclear plants just as (I assume?) a jobs thing. Exelon doesn't seem to be pushing that hard to keep plants it already owns online.
Right, I just mean the politics, technology and economics interact particularly strongly with nuclear energy. Illinois is, like, the France of US state nuclear energy production but the actual France makes money exporting nuclear-generated electricity.
Reading the Wikipedia pages for these plants, many are slated to be decommissioned and some have uncertain futures due to economics; natural gas appears to be outcompeting nuclear in Illinois. Which goes towards explaining why there aren't new plants being built: they're hugely expensive and are not reliably profitable.