- aging power plants, we haven't build any in a long time and many are now passed the initial lifetime expetency, but can't be shutdown as they should since there is no replacement ready

- price not taking plants destruction into account. None have been fully destructed yet, so we don't know how much it coat exactly but it's far from cheap since you have tons of midly radioactive material to treat

- still no proper way to dispose of the waste. There research etc, but right bow we're basically storing lots of materials that will be radioactive for millennias

- new generation plants project (EPR) is many years late and many times over budget because of critical defects in components.

- probably other arguments I forgot

I am personally undecided on the matter, but what is certain is that nuclear might be the best solution we have, but it certainly isn't without downsides.