I'm not sure the problem with the media is an age thing as much as a wealth thing. Wages for journalists are at rock bottom at the moment, and media publications are losing a fairly large amount of money due to the increased use of adblockers and competition from free internet sites. So the only people who can afford to become part of the established 'media' are the already well off types.

So the people who'd argue for change can't afford to live on the wages provided, leaving only the people with a decent amount of money in the bank (and who usually trend towards having more conservative or authoritarian views). It might also be why journalism isn't particularly diverse in terms of who works in the field (despite what some of them like arguing about), because non minority candidates tend to have the support networks to fall back on to continue working in the field.

If there's a predominance of older people at the higher levels in the media world on the other hand, I suspect it's because getting rich in this industry was a lot easier before the internet was a big thing. Most of these people started when anyone wanting visibility had to go through the old media gatekeepers...