Interesting point, and I happen to have worked with the internals of ffmpeg on the job, so I understand. (I gave it a plugin architecture, supporting dynamically loaded AVParser and AVCodec objects, supporting hardware acceleration.)

I dunno. Statements like in the link make me question if someone is actually competent.

someone's grasp of best practices in vcs is in no way an indicator of their programming or cs abilities

But it could still be an indicator of competence.

To reason about software, it's a useful cognitive tool to be able to simplify gigantic systems down to interfaces and black boxes.

Carrying that notion of isolating components too far, such that you don't consider human cooperation as part of the system? It happens often, but we also often distinguish this with statements about EQ versus IQ rather than summing it all up as competence.

(Yes, you used the word indicator. I'm speaking to the community more than you specifically.)