Indeed, the given strawman alternative languages (Ruby and Python) are far, far worse for productivity. Python changes are totally unreviewable since one cannot in any way reason about the correctness of a function call without reading the definition of the function itself, and all the functions to which it passes the arguments, all the way down, which of course takes forever. At least with C++ you can reason that if a change compiles it has not made any dramatically stupid type errors. You still need to think about whether any unnecessary temporaries or copies were made, or questionable assignments, but you need only think about that one level deep. Is seems to me far more dangerous to suggest writing new code in Python.