I believe that the excitement came by the fact that such small particules are extremely hard to produce. And HPQ has a cheap and scalable way to produce them.

The very small size is a way to solve some issues that comes with the use of Silicon material when getting charged with electricity. With this milestone, they are prooving to the industry that they are the best positioned company (or one of the best) to produce these partocules which should be in high demands by EV and battery manufacturers

I hope it helps, thanks