AFAICT, the main problem is that android doesn't force the autofill provider to partition data according to which application is in use, in the same way that yo

AFAICT, the main problem is that android doesn't force the autofill provider to partition data according to which application is in use, in the same way that you would expect them to be partitioned based on domain name on the web. However, the information (application_id) is provided to the autofill provider, so it's not really fair to say that android itself is vulnerable: specific implementations of the provider may be vulnerable. Even if android could protect against this specific issue, you're still going to be placing a lot of trust in the autofill provider.