I agree that having stricter coercion rules makes sense in situations where the coercion might be ambiguous, whether adding byte-strings and Unicode strings tog

I agree that having stricter coercion rules makes sense in situations where the coercion might be ambiguous, whether adding byte-strings and Unicode strings together is such a case is debatable though (I think it is), as in many cases implicit conversion yields an acceptable outcome. Again, this is more a question of design philosophy, but the thing with Python (2) is that implicit coercion was the default behavior in many cases, so changing that is painful. Personally I think we should double-down on type annotations and stronger (optional) typing for Python, because the lack of a good type system is by far the biggest obstacle for building robust, large systems in Python.