Python is very strange programming language for a MMORPG. I'd imagine they would write it in C++ or something. They don't quite explain what they use it for.

And yeah, using a faster but safe language could help immensely.

Python is just a part of the tech stack, there's also a lot of C/C++ code. How much Python vs C/C++ is hard to say from the outside though, but the parts that have been open-sourced are pretty much all C/C++:

https://github.com/carbonengine