For the record, I'm a fan of both Python and Julia (though, I believe that the latter is not yet ready for general programming mainstream industrial use). As for Python "stagnating as a scientific programming _language_", it is totally understandable. It tries to be the language of choice for everyone. However, as we know, "you can please some of the people all of the time, you can please all of the people some of the time, but you can’t please all of the people all of the time".