The lack of electronic components led to this and too many people wanted the PI4 in relation to the processing capacity of the factory.
I wanted to buy a home NAS for myself. Then I found other possibilities: Orange PI, Banana PI, Rock64, Odroid XU4 and others.
However, I found a thin HP client and made a NAS on Linux OMV from it. The fact that the Rasberry PI is not bigger and consumes a little more energy is about 45 W, but there is a CPU with 2 cores, 4GB RAM, Gigaport, 2TB HDD and the system runs on a small 32GB SSD found at home.