How exactly does Youtube have a monopoly on video? What's the underlying scarcity they're exploiting?

Well, they are the de-facto curator of the bulk of our civilizations videos. Lets be honest, if you aren't on YouTube your chances of being searched/promoted/seen are greatly diminished. Maybe to nearly zero.

The only video content I can remember paying for has been on vimeo and udemy.

But then again I'm old fashioned and like to read about stuff on some web site and then click to whatever video hosting site they use.

Ad placement via search results dominance.

That's so far from true. A "video hosting services" search away is >10 results, of which I recognize at least 3 as professional level excluding Youtube (Vimeo, Ooyala, and Wistia). They may not have the entire ecosystem around it, but you need to be a little specific if you want anything approaching a valid claim for "monopoly on video" _hosting_. If you're talking about traffic, that's a separate story and is only a sign they are generally providing a usable product.

When I search for video on search engines, I only see hits to YouTube and far far fewer hits to Vimeo. I never see hits for Ooyala and Wistia; honestly, you could be making those sites up for all I know.

And the other ones won't ever see more popularity if everyone keeps saying that YouTube is the only game in town, and doesn't start using the other sites.

They don't have a monopoly - what an absurd idea. You can just publish videos on your own site.

Microsoft didn't abuse a monopoly on Windows in the 90s either, as you could just run a Linux distribution on your own machine. Right? Wrong.

https://en.wikipedia.org/wiki/United_States_v._Microsoft_Cor....

Just because someone can run a small-time operation out of their garage, doesn't mean another company doesn't have a monopoly.

Ms had a monopoly because of market forces - but it's very easy to not use youtube.

As a contributor or as a visitor?

Quoting from that article: These spaces are usually the product of a deal between cities and private real estate developers in which cities grant valuable zoning concessions and developers provide in return privately owned public spaces in or near their buildings.