Gstreamer is increasingly developed in Rust, and is a far saner, better documented and more flexible framework for developers than libav/ffmpeg.

The pipeline/plugin based architecture is pretty neat even as an end user, I find it a lot more discoverable.

Gstreamer is a high level API that uses FFmpeg, not a FFmpeg replacement.

This is just blatantly wrong, as anyone that has actually looked at the project's documentation and code can tell.

Because GStreamer is designed to be modular and plugin-based, all sorts of plugins exist for it (including libav plugins) but it is itself a media framework that is quite capable of replacing ffmpeg. Neither is "higher level" than the other.