The idea of SMR is not new in Nuclear reactor technology. SMR would suffer from "Economics of scale" that if we try to double size of SMR, it would be expensive than the bigger one with the same MW output as Levelized Cost of Electricity (LCOE) (SMRs might not improve in economics compared to large reactors --> CAPEX and OPEX). From Nuscale project, I am not sure that it would be called as "successful project". for mass production - it would never happen for a nuclear power plant. Each nuclear plant needs a custom design (cannot design identically). A one-size-fits-all design would be way too expensive and overbuilt.