related question to @Jemaclus above - why is C++ the popular language for gamedev? not C# or some other higher level language. is it only for when you're working on console games or does it also matter on desktop games?
Unreal Engine uses C++. You have boost, SDL, Ogre3D, Irrlicht, EnTT, ImGui, etc... aka: C++ has a good ecosystem for gamedev.
The "Zero Cost Abstraction" philosophy of C++ makes it easier to squeeze out the performance you want.
Unity (and recently Godot 4) uses C# but they are still relatively young in the field. We were making games long before those :)
I would not say it's "THE" popular language, but it does have an history.