Efficiency doesn't matter nearly so much as is usually assumed.
What matters is cost. Exactly, cost per Wh stored, and per W in and per W out.
Mineshaft storage is very, very efficient, but has an upper limit on energy per mineshaft determined by its depth and how much weight fits in it. The cost of the winch apparatus is amortized over that amount. More mineshafts means more total storage.
Pumped hydro has very, very low cost per Wh stored, but kinda high per W in and out. But thousands of pumped hydro systems were already built, almost, so seem free; they just needed pumps added.
Synthetic H2 and NH3 are very, very cheap per Wh stored. W out uses existing turbines, so seems cheap. W in depends on your electrolysers, which are improving fast.
In batteries, cost per Wh stored has been large, but is different in different chemistries. In a better chemistry it is lower. Flow batteries have lower cost per Wh stored, for any liquid chemistry, but higher per W in or out; and need plumbing and pumps.
Details matter. Numbers matter. Dumb choices make dumb designs. Dumb designs can be improved on.
Drawing conclusions based on dumb choices is just dumb.
Musk is dumb, but just barely smart enough to hire smart people and, sometimes, let them be smart. So, Hyperloop was just dumb, no matter who works on it. Starship is kinda smart, depending on what you can think of to do with it. Mars colonization is dumb. Starlink could possibly be smart, depending on a lot of details.
A wholly new capability, like radically cheaper mass to orbit, can often enable smart ideas. Super-expensive mass to orbit was good enough for weather satellites, planetary probes, and geosynch COMSATs.