There's "arguments of authority" and then there's "accusing Walter Bright of having never written a line of code before".

AKA: Conflating authority with expertise

What argument from authority is being made by anyone?

The GP decided, out of the blue, to accuse the author of never having written a line of C code in his life. That's kind of inappropriate in any context, IMO, but just downright laughable when the author is well-known for singlehandedly writing several compilers and a whole new language.