Don't overthink it. The article was probably translated from Dutch, or done by a Dutch person, and there isn't direct equivalent for "listings" in Dutch.
If there isn't a distinction between ads and listings in some language, isn't that more evidence that both are actually the same thing?
Some cultures don't distinguish between green and blue and don't have a word for blue. That doesn't mean that blue is the same as green.
Another example is that in some languages they just have one word for ”leg” and ”foot”, and one for ”arm” and ”hand”. But obviously in English there’s a distinction.
That's interesting. So how would a Dutch person describe Google search results listings with ads in between?
They'd call them "search results" (zoekresultaten).
FWIW, real estate listings are "advertisements" here.
same: search results with advertisements (zoekresultaten met reclame)