Over eight years.Since 2015, Apple doubled RAM, doubled storage, and lowered the MSRP when accounting for inflation.
But compare that to the changes between, say, 1984 and 1992. Or between the previous or following 8 year windows.
And so looking at 2024-2032, can one expect a reduction in price/GB? Probably, a small one, but only a small one. And guessing the actual year of change is going to be hard.
All the whining over Apple's base specs of 8GB RAM are not going to change that.