Are text ads similar to organic listings?

Yes, text ads resemble organic listings. According to the document, text ads add value on top of organic listings because the ad's message is determined by the advertiser, whereas the organic listings' snippet is determined by Google.

Moreover, control over appearing on the search engine results page is stronger for text ads, as advertisers can bid high to ensure visibility, unlike organic results where control is weaker and depends on search engine optimization efforts that take weeks or months.