Unlike, say, Linux programming where C is the standard, almost all games have been written exclusively in C++ for a long time now, probably three decades.
Also, three decades is going a bit too far back, I think. In the mid nineties, C was still king, with assembly still hanging on. C++ was just one of several promising candidates, with some brave souls even trying Java.
Which is why after so much resistance not wanting to use the NDK for Vulkan, and keeping using OpenGL ES from those devs, Google is bringing WebGPU to Java and Kotlin devs on Android.
Announced at last Vulkanised, there is already an alpha version available, and they should talk more about it on upcoming Vulkanised.
My memory was wrong: I was thinking of the Quake 1 engine, but I just looked it up and it’s C with some assembly code, no C++. The reason I remember it being C++ was because Visual C++ was the compiler tooling required on Windows.