Could a bird-sized consumer drone be digested by a jet engine, and not be recognized as a drone, mistaking it as a bird strike?
I would assume a major factor is how the engine handles the drone, in terms of defects or runing anomalies.
The battery comes to mind, hitting a turbine blade might be a problem - depending on the battery size.
There are certainly drones with very small batteries, that I assume will do no obvious harm, and certainly ones with batteries big enough to do harm for sure.