One other problem with nuclear is that it has to run at a fixed output level, and can’t be scaled down if there is eg. lots of solar power being generated. In this case, you have to scale down renewables to make sure you can use the nuclear power, which makes it clash with the eventual goal to power everything with renewables.
As far as I can tell, there is no time with no sun AND no wind: https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Energy_statistics_-_latest_trends_from_monthly_data
In fact, there are multiple studies claiming that you can very well supply base load with renewables, for instance this one:
https://www.ceem.unsw.edu.au/sites/default/files/uploads/publications/MarkBaseloadFallacyANZSEE.pdf
One other problem with nuclear is that it has to run at a fixed output level, and can’t be scaled down if there is eg. lots of solar power being generated. In this case, you have to scale down renewables to make sure you can use the nuclear power, which makes it clash with the eventual goal to power everything with renewables.