You might consider it a trivial observation, but the economic and physical implications are not trivial. They still cost money, and the physics still don't work if you don't consider them. Any discussion of the cost or viability of a generation source must include the cost and viability of augmenting the weaknesses of that source to address these deficiencies. Anything else is wishful thinking at best and magical thinking at worst.
The physics of practical storage have been fully understood and well internalized in civil engineering for centuries: E = Fx. All that remains unclear is which forms will turn out to be cheapest at the time when they need to be built.
What is known now is that costs are falling even faster than did solar and wind, and are already of similar order.
