The whole point of the manual cleanup duty is the meticulous mapping of MOOP. This information is used by the community to learn and improve for next time. This has resulted in measurable improvement over the years, despite the event growing massively in size during that time.
I feel a big commercial machine that cleans the site up in a couple of hours will result in a community that does not espouse the 'leave no trace' principle. Because why would you care? A big machine is going to clean it all up anyway.