You're very much misrepresenting the facts. Android very much encrypts data (or gives users the option to, I'm not certain if it's the default). Chrome, the desktop application, does not. Why? Because that's a false sense of security. Chrome would have to also store the encryption key, and store it in the same place and under the same access controls as the encrypted data. This is not real protection. It is up to the user to not run malicious apps under the same security context as Chrome, and to encrypt their hard drive to protect their data at rest. Nothing that chrome can do in its security context is anything more than placebo - as shown by the fact that malware (and legitimate programs!) can read the Firefox local password database.