It's funny because back when they first did it for a few seconds, I was confused as hell, because I'd thought we'd already been saving antimatter for years. Mostly because of some really old article I'd read years ago (late 90's early 00's) describing "advanced forms of space propulsion that use current existing technology" an one of the options was some form of antimatter propulsion, saying we already stored small quantities gained from particle accelerators (I guess this turned out to be wrong!) and could accumulate enough in a decade or two to run such an engine.
This wasn't like, a Star Trek antimatter engine. Just a dirty one that could go a good bit faster than existing chemical-based rockets. Fast enough to make Saturn/Jupiter missions viable with a flight time of 5+ years.