A big part of the cost is design. China has built a lot of nuclear capacity at a low cost by essentially copying and pasting the same design, something that should be even easier with SMRs.
Relatively low cost. The cost of PV has dropped much faster and they’re building much more of it, even compared to their plans from a decade ago. SMRs are supposed to be the design that solves this, essentially moving nuclear into the same “build it at mass scale in a factory” footing that solar PV is on. But solar is deep down the production curve and SMRs are just beginning it.