What we have here is the Ram 1500 DT Series. It went on sale in the US in 2019 but turned up in an official capacity in Australia from mid-2021.
This new shape Ram 1500 DT Series is sold alongside the earlier Ram 1500 DS Series (also known as the Ram Classic in the US).
Ram Trucks Australia is selling the new and old models alongside each other for the foreseeable future to give the brand a broader price range.