Why nuclear surface warships are not a simple submarine extension

Why did Britain not extend nuclear power from submarines to more surface warships?

Surface ships need different reactor arrangements and a costly new industrial base, without a sufficiently strong requirement.

A submarine reactor cannot simply be transferred into a surface warship programme. Surface ships need different reactor arrangements, training, support, and industrial investment. Britain had no requirement strong enough to justify building that second nuclear-propulsion system. The Queen Elizabeth-class carrier discussion shows that the option received serious consideration before cost and need pushed it aside.