Analogue consoles still are emulating the old game consoles, but they do so in a different way than a normal software emulator. This emulates the individual circuits of the device on a special chip called a FPGA. This has the advantage of supporting much lower input latency (say with real controllers) and video latency (down to the cycle for CRTs). This means your lightgun will work on a FPGA NES with connected CRT, along with making the system “feel” better (due to the lower latency).