I don't think it's stagnant. I continue to see stuff like small modular reactors making progress. The obvious reason why it doesn't get more play is because it doesn't serve anybody's political goals. Renewables and carbon taxes or other measures to try and reduce quality of life (or opposition to those) get attention because they have good political value. Actually spending money and generating sustainable power, no…
Small modular reactors don’t actually solve any significant issues for the nuclear industry. Construction costs are dwarfed by operating costs and the idea that N small reactors with N times as many parts will somehow require less maintenance is wishful thinking. They very well could be slightly cheaper over the first 15 years, but nuclear reactors are designed for ~50 year lifespans and are really expensive to decom…
Nuclear plants are cheap to run once you have them built, but they are expensive to build when everything goes right and frequently they don't.
There has been a lot of hand-wringing about the costs of the nuclear fuel cycle and frankly it's a bit ridiculous. For instance, they were expecting Yucca Mountain to cost $100 billion to run back when they were planning to run it.
People look at that and think "that's a lot of money" but a nuclear reactor makes about $500 million worth of electricity a year so that is 2 years worth of electricity from the 100 reactors that operate in the US.
(It's more absurd that we'd bury nuclear waste in Yucca Mountain when 98% of the energy content of the fuel remains in the waste! A reprocessing cycle would cost "more" but not much compared to the capital cost of building the reactors.)