From what I understand, this isn’t so much a “dragnet” operation involving combing through mass quantities of records on demand; it’s more like “this person is in public in my field of view, and I want to know who they are.”

More importantly, though, the cases so far have focused on the investigative activity that follows once a suspect has been identified. Here, we’re talking about de-anonymization: identifying one or more individuals who occupy a public space. AFAIK, the Court has never established a reasonable expectation of privacy of one’s identity in public. That will be a steep hill to climb.