Not quite true: there is no public opposition to anything in Russia let's say, and they build their nuclear plants for about that long. Belarusian NPP construction started in March 2011 and first reactor went online in November 2020, 9.5 years. Chernobyl NPP was probably built faster than it should've been given many issues they introduced in the process, and it took 7.5 years from commencement to first reactor going online, May 1970 to December 1977.

10 years down the road, there simply won't be a place for non-renewable power left on the market, apart from natural gas peaker plants for grid balancing. Too late to start any new ones.