Are there that many unique porn sites? Seems like you'd have to be doing things like counting every pornographic tumblr as a unique "site" to come up with a nu

Are there that many unique porn sites? Seems like you'd have to be doing things like counting every pornographic tumblr as a unique "site" to come up with a number that high. For purposes of figuring out who is tracking you, should an entire platform count as 1? From the paper's methodology: "In March 2018, we used a U.S.-based computer to analyze 22,484 pornography websites to identify the third-parties which may be able to infer users’ sexual interests, and whether privacy policies provide a sufficient vehicle for obtaining meaningful consent to tracking. To create our population of pornography websites, we downloaded the homepages of the one million most popular web- sites identified by the Alexa service. Upon downloading the home- page, we extracted the page meta description information (a short summary of the page’s content provided by the site developer) and page title. Our population of pornography websites is comprised of sites with ‘porn’ in the URL, meta description, or title of the page."