>415Hz is often used for baroque music but that's just a modern convention, there was no such standard in baroque times

415Hz is one modern semitone below the standard 440Hz. Many (but not all) baroque instruments were tuned slightly lower than modern ones, and 415Hz is the most convenient slightly lower tuning that retains compatibility with modern instruments by transposing down a semitone.

TIL, thanks.

The 2nd point stands though. A person with good or perfect pitch will quickly tune to another frequency.