He calls the newfound tech “Mysterious Components” and notes that these are what Team Rocket have been using to take over PokéStops over the past few months. He also notes that Team Rocket grunts have been dropping these when they’re defeated, which means that’s how we’ll likely obtain them in the future.
It’s unknown what the Mysterious Components will be used for, but Professor Willow did go on to confirm that they must have a use outside of turning PokéStops.
Some players are speculating this could have to do with Arceus, as it looks similar to the Alpha Pokémon’s plates that it needs to change typing, though it seems unlikely, given that the plates are more slate-like and involve no technology.
The last Team Rocket reveal we got in Pokémon Go showed the three admins of the group, so this may have something to do with them, but it’s all still up in the air.
More updates from Professor Willow will explain more over time, and we can likely expect whatever this is to be fully explained after this year’s Halloween event ends.