Antimatter is a unique element: nothing else can do what it does. The game changer would be producing industrially useful amounts for further experimentation.

(Antimatter chemistry would be incredibly interesting and quite possibly a practical way to actually use antimatter - shoot the beam into a reaction or solid matrix to do interesting reactions due to the electronic properties before it annihilates).

This substance can basically only do two things.

1) whatever ordinary hydrogen can

2) explode violently on contact with matter

Sure it's interesting to test 1) from a physics research point of view, but 2) is the only practical application that I know of.

I am far from a domain expert, I only know of four current and speculated uses for antimatter: energy storage, inducing nuclear reactions, medical imaging, and one specific tumour removal method.

For the first one, antimatter has about 1000x the energy density of fission, but also unlike a fission bomb all of it reacts (with an equal mass of normal matter), which means 1 gram of the stuff is a bigger boom than Fat Man and Little Boy combined.

Fortunately, "15000 antihydrogen atoms" is a factor of 4e19 away from 1 gram, and even if it wasn't we'd probably have to fuse the antihydrogen into antilithium to hold that much in a not completely absurd storage system.

Inducing nuclear reactions might make for some interesting propulsion systems, or might make atomic weapon proliferation even harder to prevent; that's expected at around 10^18 (the microgram level), which is still 1e14 more than announced by CERN — if it works, this use is hypothetical because current production is so much less than that: https://en.wikipedia.org/wiki/Antimatter-catalyzed_nuclear_p...

Medical imaging is already done with positron sources (doesn't need complete antihydrogen atoms), and antiproton beam therapy doesn't need the antiprotons to be turned into antihydrogen at any point: https://home.cern/science/experiments/ace etc.