The problem is that once this location data is available, it's easily abused by the police. Here are some quotes for you:

That's what, Cory Hutcheson, ex-Sheriff of Mississippi County, MO, is accused of doing; prosecutors say that for three years, Hutcheson abused Securus's system to track all kinds of people — even a local judge — without a warrant. https://boingboing.net/2018/05/12/extraordinary-access.html

While many departments require warrants to use phone tracking in nonemergencies, others claim broad discretion to get the records on their own, according to 5,500 pages of internal records obtained by the American Civil Liberties Union from 205 police departments nationwide. https://nyti.ms/450FPqK

U.S. Marshal Adrian O. Pena allegedly abused the Securus system by simply uploading blank documents and pretending he had authority to track people he had personal relationships with and their spouses. https://www.vice.com/en/article/k7bqew/us-marshal-securus-ph...

The issue is that most people don't want to live in a surveillance state. It's not about solving or not solving crime, it's about how much police can encroach into the general public's lives. That's what warrants and probable cause are for: to allow the police to get the job done while protecting the general public's privacy/integrity. Otherwise, you might as well go back to the middle ages and deploy the royal guard. The issue at present is that private companies, typically fueled by the advertising industry, have spawned to collect and record literally anything of potential value. Then police get access to this data, often with warrants, but also often without them. See, e.g., Amazon's Ring, or all the other examples in the other reply to your comment.

I think there are basically two questions here:

1. Whether this kind of unrestricted bulk data collection (i.e., mass survaillence) should be allowed in the first place.

2. If it is allowed (presumably because the benefits outweigh the downsides, which isn't my opinion), what controls exist to access the data, what oversight exists, and who enforces it.

The current state of things is basically a free-for-all, where any collection goes, police often work in the shadow, and corporations get, at most, a slap in the wrist.