Nuclear has been at that supply level since the 1970s. Other parts of the world have much higher renewable mixes in their energy inputs. For example, Germany:

https://www.reuters.com/business/energy/germany-likely-pass-50-mark-renewable-power-this-year-minister-2023-09-18/

Nuclear is not necessary to meet climate change targets. In fact, it’s so damned expensive to deploy and maintain, it will harm meeting those targets.