You’re correct about renewables being cheaper… but faster is a more nuanced discussion.
In the Canadian province I live in we generate 70% of our electricity with natural gas fired power plants. Roughly 20 TWh annually.
To replace that 20 TWh/yr with solar power, we’d need to build ~150 more solar farms the same size as the largest solar farm in Canada. Plus enough storage to cover the grid at night or when the weather is cloudy.
To replace that with nuclear power, we’d need 2 plants the same size as the smallest nuclear power plant in Ontario.
The nuclear plants are significantly more expensive than the solar, that much is certain.
But there are logistical limitations on how many new sources we can interconnect on the power grid in a given year. We simply can’t connect that much new renewables quickly.
It doesn’t need to be a choice, we can do both renewables and nuclear. But if we want to get off of fossil fuels in the next decade, nuclear will get us there sooner.