While weight is a significant factor it's not as important as rigidity. Compare getting hit in your head by a 1lb bag of feathers compared to a 1lb brick.Show or not show the result will probably be not good for drones. The blades of a jet engine are of stiff material and as it must light as well it is prone to brake at high speed impact with any object. The soft tissue of birds may do less demage then the stiff object but all depends of it's weigt.
It would be interesting to know which craft would get more harm the jet or a propeller driven
The blades can withstand a lot but insanely tight tolerances of the components and the rigidity of the motors/battery of the UAS will most likely cause considerable blade damage/distortion and at speed cause failure throughout the unit.
Here's a video showing what a single blade release can do to the jet engine at operating speed.
A Goose (really any bird) is very frangible but many components of the UAS (motors & battery) are not.