No he didn't forget. The lower layers, yeah it probably will be in C (but it doesn't HAVE to be). But in the application layer, it probably shouldn't be.

If things like memory management are not the first priority when writing every line of code, then you shouldn't be using C, and that's really the only reason you should be using C, when there's a specific need for memory management.

Not surprisingly, this is exactly why the world has moved beyond C for the application layer, it's painful to have to think about that stuff constantly, so people just don't (this being an example).