Well, no, not really.
The original ball joints were riveted to the stamped part of the control arm. When the original ball joints get replaced, it's a PITA to drill/grind/torch/press out the four rivets. The replacement ball joint comes with bolts instead of rivets for ease of re-assembly.
From then on, replacing ball joints is fairly easy--just unscrew the bolts once the ball joint is free of the vehicle.
This isn't "new" with the GMT400. I had a '66 Chevy Biscayne, and a '66 Olds Toronado that had riveted ball joints, when they were replaced, the new joints bolted in place. I bet the riveted ball joints go back long before that (but I've never done ball joints on a '30s, '40s, '50s car or truck to have any first-hand experience.)