Android can disable these alerts using ADB

adb start-server

adb shell pm disable com.android.cellbroadcastservice

Edit: AND

adb shell pm disable com.google.android.cellbroadcastreceiver (This is the Wireless Emergency alert app specifically)

Caveat:

CellBroadcast is a feature of the Android Open Source Project that allows devices to receive and display emergency alerts from cellular networks. Learn how to implement CellBroadcast in your device, how to configure the broadcast channels and languages, and how to test the functionality with the CellBroadcast app.

This is the app code that provides these alerts.

https://source.android.com/docs/core/ota/modular-system/cellbroadcast