When you look at typical FGPA emulator source code, it often looks pretty close to software emulator code ported to VHDL/Verilog instead of an attempt to re-create the original reverse-engineered 'transistor-level design' which would automatically reproduce any 'undocumented behaviour' of the original chip (like http://www.visual6502.org/JSSim/index.html)

As such, an FGPA emulator isn't necessarily any closer to the original hardware behaviour than a software emulator. I guess the main advantage of FGPA is better performance on lower cost hardware.

Many people think an FPGA is automatically accurate emulation because it's "hardware" and the original console is "hardware".

But the FPGAs are based on C software emulators because that's where all the knowledge in the world of how to emulate the original system is kept. You can't translate original hardware to Verilog and skip the figuring out how it works process.

You're getting into the weeds and will get different answers based on semantics, here.

A FPGA emulation isn't inherently better than a CPU-based emulation of any given chip; it's not more authentic because it still lacks the particular quirks of any old CPU that are associated with the way the hardware was laid out, path lengths, imperfections etc.

I'm glad it's introducing FPGA programming to a wider audience because FPGAs are probably going to become more important going forward - and are probably going to be what keeps Intel alive - but it doesn't make the emulator inherently better.