> Cell towers are monitoring a public broadcast from a beacon you voluntarily carry on your person.

It's an encrypted broadcast, not a public broadcast. This is why the police needed to ask the mobile service providers for this data. It is not public.

> For some reason querying that dataset requires a warrant but querying a broadly analogous dataset from the operator of a network of cameras doesn't?

The data is not broadly analogous. One is encrypted radio traffic. The other is unencrypted, and you can record it yourself with a pen, paper, and the Mk I eyeball. This is why the "plain view" doctrine applies.

Again, the courts have already ruled on the use of ALPRs. The defense tried to use US vs Carpenter in US vs Yang, and the courts did not accept that argument that ALPRs are analogous to cell phone location data.