The question then becomes, why start out trying to learn something by ear? Is it not less work to start out sight-reading something, commit it to memory, and then play it by ear? That would assume one knows how to sight-read.
That assumes you can get a good transcription of what you're trying to duplicate.
These days, stem splitting software is much better than it was, so you can hear parts that were buried in the mix. So learning by ear still has an edge there.
Plus, the person who came up with the part in the first place wasn't reading a transcription of the part.
It also means you
care about being able to duplicate something exactly. That's never been a goal of mine. If I can play the part so the arrangement works, I consider it a success. YMMV, which is one of the many, many reasons I'll never be in a cover band.
