This system is based upon Low-Cost UAV Swarming Technology (LOCUST) which was developed by the US Office of Naval Research. The important point is that this is a low cost system and we know that TWDC is all about saving money. This is going to save them a lot of money on fireworks. Plus there are storage, safety and security problems with fireworks that would be eliminated with drones.
The biggest factor is the noise, water air pollution caused by fireworks. Drones will eliminate those problems as well.
The new technology is cheaper, safer, and eliminates significant security and pollution problems. I feel confident TWDC will continue with this new technology.
https://www.inverse.com/article/23975-disney-intel-drone-show-locust-military-tech