No. While both cards are issued by American Express, the Amex Platinum card is a premium travel rewards card that earns Membership Rewards points, while the Delta Platinum card is a co-branded airline credit card that earns Delta SkyMiles.
The Amex Platinum card comes with a long list of premium travel and shopping benefits/protections. The Delta Platinum card comes with benefits that are more Delta Air Lines-centric, such as a free checked bag, priority boarding on Delta flights, and a faster path to Delta Medallion elite status by spending on the card.