It's not. It's made now, but if the anime was made in the 1990s, the show would probably look something like this. [Image: salvamakoto | Deviant Art]
On Deviant Art, the incredibly talented Salvador Vera has uploaded some images of Dragon Ball Super done up in a Dragon Ball Z art style. The results look fantastic. But first, this might help explain the difference.
[Image: salvamakoto | Deviant Art] And now for a DBZ style take. Dragon Ball Z, of course, was broadcast in Japan from 1989 to 1996 and still looks terrific to this day.
Here are more of Vera's 1990s reworking of Dragon Ball Super.
[Image: salvamakoto | Deviant Art]