Maybe we should go after the Apple Pickers....

Carriers have had the ability to block stolen phones by their unique electronic serial/identification number since the early 90's.

Their primary reason for maintaining this universal stolen phone database back then was their mutual liability for fraudulent roaming charges and their desire to block phones associated with accounts closed for nonpayment.

With the reunification of the original "Ma Bells" during the Clinton and Bush administrations they effectively eliminated roaming charges and any resulting liability for them.

Without financial liability the carriers have no substantial motivation to police all of the stolen phones anymore unless the actual police or one of the multitude of government intelligence agencies requests that they do so...which is rare because they also usually prefer stolen phones to remain active and in use.

Of course, if you don't pay your bill carriers will still block your phone because they have a financial incentive, the legal freedom, and a huge spiteful desire to do so.

Since an active stolen phone generates revenue for the carriers through its new user, through the victim's purchase of a new phone, through new service contracts or contract extensions, and through purchases of worthless insurance by victims, the carriers have little, if any, financial incentive to block or help recover a stolen phone. However, they will still block a stolen phone associated with fraudulent use...again, because of nonpayment for service.

In other words a stolen phone already gets blocked when it affects the carrier, just not so much when it affects only you.

If you want to avoid having your phone stolen, use a slightly older phone or a less popular phone than the latest iPhone or Samsung Galaxy. Use a case that helps conceal the phone's make and model. Don't use it or lay it down mindlessly in public. Assign it a space on your person, in your vehicle and in your home and return it there after each use so that you know where it should be.

Also, don't store valuable personal data (contacts, photos, maps, browsing history, location history, etc.) with the phone's standard/default apps, especially on Android phones; encrypt and store your data files on a removable SD card with one of the more secure apps that add this functionality along with an encrypted backup of your data to a cloud drive. Use security apps that block tracking and wipe your usage history. In fact, these days you can even create your own secure, encrypted cloud drive using open source software; try it.

Until the day comes when users truly own their smartphone (trust me, you don't), the thieves who take possession of your actual phone are nothing of real consequence compared to the multitude of thieves who have access to your phone and your life when it's still in your hands.