You become a recruiter.

Identifying dev talent is one (very important!) part of the job for dev managers, but not enough on its own to be successful.

The only pure application of that skill would be as a recruiter.

That said, you're almost certainly wrong. I can't find the quote/citation right now, but distinctly remember that over a decade of data at Google showed that only one person at the company was really individually exceptional at predicting performance as an interviewer (and he was a special niche case).