This is pretty much the definition of "cruft." An accumulation of old defunct artifacts in the face of technological advances. [0]
[0] http://catb.org/jargon/html/C/cruft.htmlSince every plant is essentially a one-off * , the economics are doomed to be terrible.
Honestly, the UN should just annoint a multinational nuclear conglomerate composed of any volunteering existing nuclear companies. Standardize designs, share R&D costs across all, then use UN-approval for non-proliferation or assistance with waste disposal as the market carrot.
It's a bit crazy that for things like space and nuclear technology we're burning so many resources (physical and human) reinventing the wheel in 5 different places, and telling smaller countries they just can't be trusted with wheels.
* EDIT: Did some background reading and apparently this is one of the features of the AP1000 and its NRC certification. It's now certified to be built again as long as the design is not modified. Not sure if this was standard NRC practice, but the phrasing and context make this sound like a somewhat new approach.
If so, they the federal government should guarantee backing of a pilot plant/upgrade so that we don't end up with these fiascos