There may be more people who use Python, but there are strange semantics that cause problems even for experienced Python programmers. For example, assign-by-reference (apparently built without considering the solutions available in MatLab & R) frequently leads to unexpected changes in the caller's space. I expect that very few people understand linearisation, so multiple inheritance is effectively unusable in Python. C++ would generate a compile-time error if two base classes provided the same method (unless they inherited it from a common virtual base class).

The text in question appears twice in Section 9 of https://docs.python.org/3/tutorial/classes.html. It's in the third paragraph of the introduction and the 5th text paragraph of Section 9.5.