Is it likely that ageism is at play in the fields of musicology and ethnomusicology? I’ve just had a look at the 2014-15 Musicology/Ethnomusicology Wiki. Including the temporary/visiting positions and the handful of post-doctoral fellowships, the two fields produced 82 full-time positions this year. Of the 73 positions for which we know the person hired and giving 2016 as the benefit-of-the-doubt-year for the six hired ABD (all but dissertation), the average PhD year is 2012.5. That number includes outliers from 1998 (someone I know), 2003 x 2 (not including me, sadly), and 2006, but everyone else who was hired in 2015 completed his or her PhD between 2008 and 2016. The most hired-from year is 2014, and the 57 people in the five years from 2012 to 2016 represent 78% of the hires.
My earlier research shows that there are around 375 new PhDs produced in musicology and ethnomusicology each year. So, the backlog of career-age music scholars who have not ended up in full-time academic employment must number at least several thousand. Lots of older scholars continue to apply for full-time academic positions, but publishing books and articles, presenting conference papers, and/or working as a part-time adjunct instructor apparently makes very little difference. Promising, newly-minted thirty-year-olds almost always win out over experienced fifty-year-old PhDs. It’s impossible to prove for sure that ageism exists in all of this, but the statistics simply speak for themselves.
If at first you don’t succeed … you won’t!