Unless there was a deleted post I didn't see, I consider this all to be "on topic". The people who are being hurt the most by the drop in ad revenue are the ones who are putting all of their eggs solely in the YouTube basket. There are lots of teams out there that have been affected little to none by the "adpocalypse" (I can't stand the phrase but at least people know what I'm referring to). If you don't diversify yourself and/or your brand in any market where you don't have full control over distribution, then droves of people will lose out if that one service changes policies or goes under.lets not get off topic here
YouTube has been trying anything and everything to become profitable (how many people do you know that pay for "YouTube Red"?) and right now, as with traditional media, advertisers are their largest source of income, but with ~400 hours of videos being uploaded every minute, even trying to somewhat properly index such works in an algorithmic nightmare. If Google hadn't bought it out years ago (I still think they paid way too much at the time, but that's moot), I think it's likely that it would have collapsed under its own weight as time went on. Thankfully Big G is a large enough company that they can afford to have a popular service in the red (no pun intended) while constant changes are happening so it's probably not going anywhere, but the same laws and rules that have affected it would be placed on any other giant service that would try to overtake it (compared to comparatively niche services which exist now that are chipping away at both content and user views).