Conal’s point is that no, in fact there are almost zero programmers that fully understand even the simplest Python code

Can you summarize the reasoning there, for those of us who are mildly curious but don't have time to spend on a podcast?

By "fully understand", does he mean knowing exactly how data are being laid out in memory, or when it is reclaimed? Knowing exactly what CPU instructions are being executed, registers used, and stack frames created behind the abstractions? Something else?

since it is a dynamically typed language.

What does Python's type system have to do with it? Python doesn't quietly convert objects of one type to another behind your back, like some other languages do.

What concerns me is your condescending tone.

I didn't read condescension in that comment. It's possible that none was intended.