Yes cheap storage will solve lot's of problems. Problem is we do not have technology for that yet which is scalable. Snow Hydro 2 is pretty much all we can do for gravity storage in Australia. Only other option is batteries. There is no production capacity to cover demand in that scale, and will take long time to build it up. And for some reason no one takes account ecological impact of building all these batteries/solar/wind turbines. They all very material heavy on per kW basis.
It is a myth that solar and wind are cheaper at scale than conventional generation. It is only the case if covenantal generation is pay for all unpleasantness of renewable instability. As soon too much renewables is in the grid you have to pay to keep it stable.
There are 3 main method:
Overprovisoning - to compensate for annual cycles. Australia is happy here as we consume more power at summer than at winter.
Long range transmission - to compensate for local weather
Storage - to take care od daily cycle.
It is all costs lots of money and not required now as it was taken care off. This is why solar/wind is cheap.
Just add power cost to run it. Old thing become way more expensive if you add power cost over it life.