This doesn’t make any sense to me. There’s no precedential issue here. Law enforcement can and routinely do demand such data, and in the case of other services

This doesn’t make any sense to me. There’s no precedential issue here. Law enforcement can and routinely do demand such data, and in the case of other services they receive it. The only news here is that Signal can’t produce much of it because they don’t have it. Signal is in fact complying with the subpoena. They’re not challenging anything in court.