It currently takes so long to deploy nuclear in the West, because the West mostly dismantled the nuclear supply chains, starting in 1990s. At that time coal and gas power plants were seen as better than nuclear power plants and no expansion of nuclear energy was expected.

For example Germany was still building new coal power plants in 2005-2007.

https://energytransition.org/2016/10/germanys-last-new-coal-...

https://us.boell.org/en/2014/06/06/german-coal-conundrum

Currently, in 2026, Germany is retiring coal power plants and replacing them with gas power plants.

https://www.cleanenergywire.org/news/german-government-appro...