Nuclear takes time but I don't think the solution is going to come through only one approach. It seems like we'll need a mix of technologies to actually solve this problem. Nuclear provides clean base load in many places currently (e.g. more than 60% of the base power in Ontario)
We have 10 years to cut 50% of emissions. We literally can't build enough nuclear plants in that time, it's very slow. It's also really expensive. We have to use other renewables.
We should a) build renewable; and b) build nuclear reactors with the idea that you will insert rods, to decrease power output when the winds are blowing strong, and restore power when the winds have dampened. Outcome, lowered nuclear waste from the plant, fewer expensive battery storage (or pumped hydro).