SMR's are what the US and China/Russia are moving towards till Fusion is viable which we could see starting at the end of this year/beginning of next. Helion is set to finish prototype number 7 Polaris which is supposed to generate the first electrons and Helion has contracts that start in 2028.

Even with cold fusion say we find it tomorrow or in 5 hours several factors remain including a supply chain for whatever is required, scalability issues of replicating and even shrinking down the size of the facility... it would take a decade plus to pull off something like that and that's ignoring any government regulations or just cutting edge technology issues they run into