I think the confusion comes from people not having a good understanding of what an interpreted programming language does, and what actual portion of time is spent in high versus low level code. I've always assumed that most of my programs amount to a bit of glue thrown in between system calls.

Also, when we talk about "faster" and "slower," it's not clear the order of magnitude.

Maybe an analysis of actual code execution would shed more light than a simplistic explanation that the Python interpreter is written in C. I don't think the BASIC interpreter in my first computer was written in BASIC.