1. Issued in relation to attempted arson, which I think we all agree fits closer with "serious crime" than "civil disobedience"
2. The warrant is detailed and specifically identifies two specific subjects, identified through CCTV footage and described in the warrant.
3. Is approved by a magistrate in a federal court.
4. Is issued for a specific location and a specific timeframe (75 minutes).
5. Is for a specific record of movements during the location and time, without account details, before the FBI asks which account details they want to subpoena.
Let's look at the fourth amendment:
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized
Was the application made under oath? Yes.
Is there a specific place? Yes, both in terms of space, and in terms of time.
Does it clearly describe what to be seized? Yes.
Has a warrant been issued by a Magistrate after review? Yes.
Sounds good to me. I oppose mass surveillance (fuck you, NSA), but this seems constitutional and reasonable to me.