Years ago I bought an Apple II computer for S$2400 and an IBM PC AT PC for $4000. ! ! !
Now you can get computers for 1/4 of that price.
Nowadays electronic components, ram chips, computers and printers are so cheap, I don't understand why the camera manufacturers don't just concentrate on FF sensors and forget about the APS-C or 1/2.23 " sensors.
If FF sensors are mass produced, I am very sure the price will drop like a stone. And from then on, all cameras will have FF sensors, much better features, superb IQ and cheaper price too !
Hope they are listening !