It would be good for Python to have more rigor in its definition. But the situation here doesn't have an analog in the Python world: there is no "PythonSpec" third-party test suite that is a) more complete than the official suite, b) exposing segfaults in previously working code, and c) going unused by the core developers.

That other languages are equally badly specified is not a good argument for why it's not terrifying.

Then again, I don't care about Python. I do care about Ruby.