The CGI was groundbreaking and a great deal more than just "backdrops". Every ship, planet, piece of debris, weapons fire as well as the interior of various parts of the station was made on *Amigas* with zero model shots. When they had enough money for a small render farm they could create large space battles in real time.
They kept the details secret even though big names like ILM and Paramount wanted to know how the hell they did it with so little equipment and a shoestring budget (we didn't see the battle of Wolf 359, only the aftermath and even that was a few years later because it was too expensive to make). They released old methods to the big studios on a seasonal basis: Mars Attacks used Season 2 quality, ST:Voyager used Season 4.
Yes, the effects look dated. Because they are. But no one else could do what they did 20 years ago.