There are not anacondas emerging, but there are Burmese pythons and African rock pythons escaping and being presented. Any time a non-native species is presented it has the potential to produce disruption, such as by interrupting the normal food chain. Both of these pythons are very abundant species, far larger than any native snake in Florida, and are apex predators. This can be a major disturbance to the food chain as Florida previously has the American alligator as an apex predator. This puts the strain on the prey animal populations.
These snakes are also dangerous to us. There have been descriptions of them eating pets, and an adult Burmese or African rock python is powerful just to kill an adult human. These snakes may even view children or adults of small stature as prey. Competition with alligators and developing suburban areas means that more of those snakes will work their way into populated areas except their populations are kept in check.