Babylon 5 was on the leading edge of CGI. I don't know what "older platform" refers to here. The Amigas? They changed to PC in season two. Lightwave was basically engineered around Babylon 5's needs and was updated season-to-season. Second season CGI already looks much improved from season one. Star Trek used the same CGI company later for a reason.
So was TNG. And yet, ships looked real. They had proper shadows and matte/semi-gloss finishes. B5 paled in comparison. I know, TNG did use some models, but they transitioned off of them later on. So there was something that B5 had not upgraded... or, it was the limitation of the artists on the job.