Listening to Jigar Shah, head of the DOE loans program, indicated part of the reason it's so expensive to build NPPs is that each nuclear power plant is a bespoke operation and requires a ton of custom work, planning and certification, etc. The suggestion he made was to create a basic design that you can just copy-paste where suitable, allowing you to leverage economics of scale. This would seem at least at first glance to align with the recommendations in the article.
[1] https://podcasts.apple.com/dk/podcast/jigar-shah-on-the-does...