My heuristic for pessimism:

We use enourmous amounts of energy and we invest enourmous amounts of money in energy production. At the same time we have neglible storage and and neglible investment in storage.

some numbers:

194MWh - capacity of Hornsdale Power Reserve in Australia

161 million A$ - it's cost (https://en.m.wikipedia.org/wiki/Hornsdale_Power_Reserve)

4 700 000 MWh - Australia's daily total consumption of energy of all fuel types (https://www.energy.gov.au/data/energy-consumption)

4700000 / 194 = 24226 - number of same power reserves to store australias power for one day.

24226 * 161 millions = 3.9 trillions of A$ - money needed to build a days capacity in Australia at current price.

(for comparison, Australia GDP is near 2 trillion A$, US GDP is 27 trilion A$)