Nothing can compete with renewable energy

[kristopher]

3. That isn't necessarily the case

Jiggle your thinking a bit and reorient your viewpoint from where we have been to where we are going. For proper appreciation of the available technologies it's necessary to look at the provision of power as an endeavor starting at the end user's location with the resources that are most suitable to the task of creating island-able microgrids.
Pumped hydro storage will certainly play an important role, but the role of "behind the meter" energy production, treatment and storage are the key to lowering costs.
With that in mind the role of end use energy efficiency, stationary batteries, and various thermal storage technologies for buildings, will determine the ultimate structure of our future grid.
I guess I'm saying total system costs will leave pumped hydro with a smaller role than it's comparative costs among storage options might lead one to believe.