The problem with nuclear is that it's expensive AND that it relies on oversight and regulation to be fully safe. What to do with the waste, how to prevent accidents like Chernobyl, Fukushima, etc.: that's the problem with nuclear. Ask yourself if you want nuclear plants in all of the dysfunctional governments around the world, given the risks we know exist. Then compare to solar and wind, which are cheaper and safer, it's not hard to see why mostly solar/wind are dominating new power additions.
I have no problems with nuclear personally, I think we should keep safe reactors running as long as our replacements would be LNG. I do think new-build nuclear would largely be deployed too slowly to help with climate change in the short run, but long-run I think it'll be an amazing source of huge amounts of power. Maybe we can have specialized reactors on-site which deal with the waste from our older reactors or from new reactors...not to mention new designs that are passively safe.