I think my understanding of yak-shaving was more, can't get to the thing you were trying to do because of cascading blockers. Less distraction, and more unknown scope and complexity.

I quite like the Malcolm in the Middle[0] example of yak-shaving, though it's a combination of both blockers and distraction.

[0]: https://www.youtube.com/watch?v=8fnfeuoh4s8