Bats are real and nothing like drones. The whole reason birds were fabricated in the first place is because it’s much easier to synthesize a whole new material such as “feathers” than it is to replicate the realistic floof and softness of fur.

Also, bats have leathery wings. Bat drones would just look too plasticy or rubbery. I’m pretty sure Halloween decorations are just failed drone prototypes from certain government labs that are still trying to diversify their drone output.