Not really, the real problem is the exponential runtime of a badly-written regex. Multithreading in CPython is also a problem, but even if this was written in

Not really, the real problem is the exponential runtime of a badly-written regex. Multithreading in CPython is also a problem, but even if this was written in a performant language with robust multithreading support, this bug could still be amplified into a denial of service.