edit: Maybe my sarcasm/snark wasn't clear: almost the entirety of the parent comment's list of stuff available to the government without a warrant actually requires a warrant.
"Police can get phone records without a warrant thanks to a 1979 Supreme Court case, Smith v. Maryland, which found that the Constitution's Fourth Amendment protection against unreasonable search and seizure doesn't apply to a list of phone numbers. The Electronic Communications Privacy Act (ECPA) — a 1986 law that underpins much of how the government can get digital data — requires providers to allow access to real-time data with a court order and historical data with a subpoena."
https://www.propublica.org/special/no-warrant-no-problem-how...
However, the stuff they can get without a warrant is enough people /do/ freak out if its applied in a manner they understand.