Facebook is a people market. Spotify is a music market. Airbnb a hotel market. Uber a taxi market Amazon and eBay... Well, literally markets, right? And so on.

Markets obviously do create wealth, as a lubricant for trade. It's a meta-level of the economy, just like money is a meta-good that makes bartering actual goods and services more efficient.

So saying that's it's all "rentier" without creating any wealth might be selling them short a bit.

Where I'm troubled is that they're not free markets, in any sense of the word. They are privately owned, and the owners try to control their markets for the sake of their own profit. That's where things get problematic, I'd say, especially when there is a monopoly.