Isn’t a monopoly just a market leader that leverages its dominant position in anti-competitive ways? The article does make a (weak, IMO) argument that YouTube is using its position to screw creators out of revenue by gaming metrics.

Monopolies are not illegal or ipso facto anti-competitive.

What's your definition of monopoly?

They're something like 75% of video hosting, and if you exclude vimeo for being paid-only then it's over 90%. That sounds like a monopoly to me.

My point is that I don't have my own definition of words!

We should all use the common definition of words. That makes communication possible!

dictionary.com gives this definition: "exclusive control of a commodity or service in a particular market, or a control that makes possible the manipulation of prices."

That's... not what I expected. To me having a monopoly means being the only provider, but I'll bend the knee to the dictionary.

In this case though, with competitors at 10% or 25% market share, you can easily publish videos at a cheaper vendor.

When the entire pool of competitors is only 10%, it's not so easy. You can put a video up but nobody will see it. The network effect of viewers is one of the big reasons to want multiple major sites.

Do you agree that Google is a monopoly? Calling Google just a market leader is the situation when the words became too blurred to carry some meaning.

Google is active in dozens of markets. It may be a monopolist in some of them.

But you can't say it's a monopoly across the board.

If Google is really a monopolist on some markets, any other market from the dozen is needed to support the Google's monopoly. Kind of Apple's Facetime when decreasing number of clients for a tiny messenger makes a big support for rest of the Apple.

I honestly don't understand the point you're trying to make.

Microsoft was never a monopoly in the personal computer market by this logic.