Just closed the account via SM. They stated that the World and World Elite are considered the same product.
Here is the text:
Our solicitations are used as a way to encourage new business
or to offer an additional account to our customers. Therefore, we are
unable to apply the incentives mentioned in your solicitation to your
existing account.
If you wish to discuss options that may be available on your existing
account, please call us.
The AA World Platinum card and the AA Platinum World Elite card are
considered the same offer.
Your account does not qualify for the Special Offer to receive Bonus
Miles due to multiple accounts opened within the past 18 months.
Please respond to this message if you are requesting to close this
account.