This is not correct based on the laws of the United States. Other people's web servers are third parties, and when you use them, your data is not protected under the Fourth Amendment.

  "The third-party doctrine is a United States legal doctrine that holds that people who voluntarily give information to third parties—such as banks, phone companies, internet service providers (ISPs), and e-mail servers—have "no reasonable expectation of privacy" in that information. A lack of privacy protection allows the United States government to obtain information from third parties without a legal warrant and without otherwise complying with the Fourth Amendment prohibition against search and seizure without probable cause and a judicial search warrant."

https://en.wikipedia.org/wiki/Third-party_doctrine