For the Z80 alone, this is true. But it also needs the Ferranti ULA which is no longer manufactured, and was kind of an early FPGA, or the Amstrad 40077 for th

For the Z80 alone, this is true. But it also needs the Ferranti ULA which is no longer manufactured, and was kind of an early FPGA, or the Amstrad 40077 for the +2A/+3, which is an actual gate array. I can imagine to get output for current display devices, an FPGA makes perfect sense as a current replacement part for these obsolete and unattainable parts.