Your link shows that China & Japan can build quickly now, and that the US and the UK could build quickly in the past. Also keep in mind that the limited amount

Your link shows that China & Japan can build quickly now, and that the US and the UK could build quickly in the past. Also keep in mind that the limited amount of data for US/UK plants are for long planned expansions. Vogtle was built to accomodate 4 reactors from the start. So Vogtle 3 & 4 should have taken considerably less time than average. But let's be generous and say that a greenfield project takes less time to construct than Vogtle, or 10 years. Do you think planning & approvals can be done in less than 10 years? Even the touted "small modular reactor" projects take over a decade. For example, the INL small reactor project started in 2013, kept getting delayed until it had a start date of 2030, and then was cancelled a few months ago. And meeting demand with nuclear would require around ~200 full size reactors. 20 years to build 200 reactors sounds extremely optimistic to me.