> Google's YouTube middleware currently occupies a comfortable niche in the bringup process required to meet that figure... but they're ultimately nonessential.
I disagree with this, though I'd love (and genuinely hope) to be proven wrong. It's hard for me to imagine starting from nothing and building up a profitable following the way people have on Youtube without Youtube's userbase and infamous "algorithm".
It might just be a matter of semantics, though. I agree that content/media existed before Youtube and will exist long after it -- but I'm not sure Youtube's niche of non-traditional content creators without the money or social networks traditionally needed to publish media could do so in its absence.
More prosaically, there's a big gulf between starting out, and reaching 1,000 true fans throwing some money at you every month. Youtube plays a pretty big role IMO in bridging that gap, and without it, only people with traditional support networks or in higher economic classes will be able to afford "doing content creation" full time.
I feel like a common response (and one sort of echoed in another reply) is "Good, let's bring the old internet back, when people did things for passion and not money". I sympathize a lot with this, but I also think a lot of content I enjoy is the product of people putting tons of time and effort into making "good content" -- time spent doing pretty miserable and uninteresting work. So I'm inclined to think the end of the "youtube era" will bring the end of a certain class of creator.
Not that I think this is preventable, since like others here, I think the whole ad thing is unsustainable, and we're seeing more and more writing on the wall. Hopefully Patreon + co. and more decentralized content aggregators like Mastodon can fill the void well enough.