The criticism of Dennis was never rational, I think it was caused by a surreal misunderstanding of technology in some people. Maybe they thought amigas were made of unicorn magic or something.
Natami.. well, is Natami.
As for the FPGA Arcade, the guy doing that has been making FPGA cores for years and has actually released various cores for folk to download and use, I guess that means he's someone with a track record of delivering.
Realistically, I think anyone that has seen people working with FPGA's would have expected someone to make an FPGA Amiga, there are some very skilled folk out there.