SMRs are still huge compared to putting $10k worth of solar panels on a house.
They also require a lot of big expensive infrastructure like reprocessing facilities, expensive safety-escorted transportation, secure facilities, etc.
What I was really getting at was the effect that low incremental cost has on the evolution of the technology. A technology with low incremental unit cost can evolve very rapidly, while high unit cost capital-intensive technologies are slow to evolve. Which will win?
Some technologies are inherently high unit cost and capital-intensive. Aerospace is a classic example, and it's why we're still flying on 1970s-tech airplanes and why rockets are just now becoming reusable. Aerospace advances at a crawl because each unit is so expensive.
They also require a lot of big expensive infrastructure like reprocessing facilities, expensive safety-escorted transportation, secure facilities, etc.