I am the author of the letter and the coordinator of the signatories. We aren't saying "nuh uh, everything's fine as it is." Rather, we are pointing out that Android has progressively been enhanced over the years to make it more secure and to address emerging new threat models.
For example, the "Restricted Settings"¹ feature (introduced in Android 13 and expanded in Android 14) addresses the specific scam technique of coaching someone over the phone to allow the installation of a downloaded APK. "Enhanced Confirmation Mode"², introduced in Android 15, adds furthers protection against potentially malicious apps modifying system settings. These were all designed and rolled out with specified threat models in mind, and all evidence points to them working fairly well.
For Google to suddenly abandon these iterative security improvements and unilaterally decide to lock-down Android wholesale is a jarring disconnect from their work to date. Malware has always been with us, and always will be: both inside the Play Store and outside it. Google has presented no evidence to indicate that something has suddenly changed to justify this extreme measure. That's what we mean by "Existing Measures Are Sufficient".
For example, the "Restricted Settings"¹ feature (introduced in Android 13 and expanded in Android 14) addresses the specific scam technique of coaching someone over the phone to allow the installation of a downloaded APK. "Enhanced Confirmation Mode"², introduced in Android 15, adds furthers protection against potentially malicious apps modifying system settings. These were all designed and rolled out with specified threat models in mind, and all evidence points to them working fairly well.
For Google to suddenly abandon these iterative security improvements and unilaterally decide to lock-down Android wholesale is a jarring disconnect from their work to date. Malware has always been with us, and always will be: both inside the Play Store and outside it. Google has presented no evidence to indicate that something has suddenly changed to justify this extreme measure. That's what we mean by "Existing Measures Are Sufficient".
[^1]: https://support.google.com/android/answer/12623953
[^2]: https://android.googlesource.com/platform/prebuilts/fullsdk/...