RE: Why can't the account password be reset?

As you can see on a password page:

The first rule of Steemit is: Do not lose your password.
The second rule of Steemit is: Do not lose your password.
The third rule of Steemit is: We cannot recover your password.
The fourth rule: If you can remember the password, it's not secure.
The fifth rule: Use only randomly-generated passwords.
The sixth rule: Do not tell anyone your password.
The seventh rule: Always back up your password.

This is decentralized blockchain-based platform and the blockchain have no idea about such thing as mobile phone numbers.