Modular nuclear power isn't proven to reduce waste storage costs, for one thing. Look at how long it took renewables to go from a theory to being a mature technology with a declining cost curve and full lifecycle experiences that make predicting cost of ownership very reliable.

It would be nice if there was a zero-carbon source of concentrated power that had a track record of being cost effective and not having nasty end-of-life surprises. This is why nuclear is seductive. But it has never lived up to expectations.