>Is there not always some sort "marketplace"

How exactly does that work for virtual products?

Catalogs - offline and on-line, commercial and government. Deprived of constant noise and overstimulation of advertising, people will actively seek such information out, whether because they have a problem to solve, or just out of curiosity. All we're talking about here is switching from current "push" model of advertising back to "pull" model.

Who here never browsed a product or company catalog they found, just because they were curious?

I can almost feel the calm just imagining the world you're describing.

Not that I ever use it but there are apparently services like https://en.wikipedia.org/wiki/Product_Hunt people use to seek out new products.

But as sibling comment said, if it's really good, people will find it eventually.

Funny you mention Product Hunt because it's pay-to-play too, there was a whole controversy a decade ago exactly now: https://news.ycombinator.com/item?id=10739875

If they provide value, people will seek them out.

How? If you don't advertise, no one can see you.

Just one counter example: gh.de

Not really a counter example: gh.de is a pure advertising platform.

If I need something, I’ll find it.

How did people that had something to sell do it before advertising?

The problem again is greed. The organic way is too inefficient so advertising needs to come in and make people rich instead of letting the product do the convincing naturally, word of mouth and so on.

Advertising is as old as humanity itself. Asking what people did before advertising doesn't make sense.

Also, word-of-mouth advertising is, as the name suggests, a form of advertising.