I would bet money that storage is a solved problem by the end of the decade, about the same amount of time it takes to build a nuclear reactor.
It's a false dichotomy anyway, because I wouldn't put _any_ money into nuclear stocks.
I also expect a lot more hydro to be built eventually, it's not as dependent on geography if you just build two ponds at different elevations for pumped hydro, or repurpose old mineshafts to get the elevation difference on flat ground.