Isn't that, at least for digital application, many chips can be replaced with FPGA, CPLD or just a good old CPU? Only recently you can see some companies repro

Isn't that, at least for digital application, many chips can be replaced with FPGA, CPLD or just a good old CPU? Only recently you can see some companies reproducing audio IC from the 80s, but not much of original work. It seems like there is a huge niche in that space, but probably companies think it is too small to be profitable.