I remember just a few years ago, the various hosts were mostly middle aged men. Now it seems like the various hosts are all under 30.
I mean years move on... people move on.
I would expect that like in a call center or office, the people in the jobs when you are 20 and they are 40 will be promoted, or retire by the time you are 45 (making them 65) and the people to replace them in general on average wont be 65 they will be 20ish... as you get older the people you work with (In my experience) will almost always get younger.
in my own life I remember the days I was always 'the kid' in the office or meeting, and now adays I look at coworkers and wonder if they are being driven to work by there parents... heck, about 7-8 years ago I took an extra job in retail (never again!!) for Christmas season and the two layers of boss ahead of me where both technicly young enough to be my son and daughter... one of my co workers (also seasonal) looked older then me (not sure of her age, I wasn't asking) and said "Look, I'm not getting yelled at for 2 minutes over on my break from a kid out of school for 3 years" and the manager corrected her that he graduated from high school 5 years ago and I had to bit my tounge not to laugh.
in my current employment (I have been here about 3 years it was precovid) I work with a boss about my age maybe a little younger, 2 women about half to 2/3 my age, a woman a few years older then me (who is looking toward retirement) and 2 kids in there late teens early 20s... my boss's boss and her boss are both about my age maybe a bit younger or older...
10 years ago some of these people COULDN'T have jobs and I know that the people who are in pictures of the team back then (only 1 remaining staff from then guess who) all look to have been my age or older... there was no grand consparicy, they just got older and left and those that came in were younger.