Comment by HybridStatAnim8

Thats are improving peoples security overall by only using pixels at this time. Nothing else currently meets the hardware security requirements except pixel devices. To use subpar hardware would set the security back substantially. They are not going to compromise on security for the sake of broad device support.

Also note that Motorola Mobility has stepped up to provide the needed hardware security features. So it will expand to a subset of Motorola devices next year.