Are you using the very latest version? YouTube changed their site again a few days ago and it broke yt-dlps ability to find all thr formats. Update yt-dlp and it should be back to normal. yt-dlp will prefer the opus when it is available by default.
Opus is much better than (YouTube's) m4a. m4a is better than mp3 (which is an obsolete 30 year old format). YouTube doesn't serve mp3 (so creating one means re-encoding), and re-encoding lossy formats always loses quality.
My guess is he's illiterate and thinks that's her real name