[teamonkey]

Gamedev - at least engine dev - bears some relation to the embedded & performance-critial world. You have this conflict between needing extremely performant code, as close to the metal as practical, but also needing rapid iteration and to represent high-level logic cleanly. This is why you almost always end up with the juxtaposition of a C++ core and an embedded scripting language like Lua.

Python isn't really performant enough, or at least hasn't been in the past. Performance still matters, even for a scripting language.

In general, if your engine does what you want right out of the box with no modifications, you can go a long way to writing a game in the scripting language and - if you're not pushing it hard - not suffer any real performance issues. But as soon as you want to chase framerates, or do something unique or time-critical or computationally difficult, which is often, you 100% need that low-level language.