Disrupting the signal is physically simple. However, if it's not under guidance and is simply following a pre programmed path then there is no signal to disrupt. And while it's simple to block the signal its illegal, so the kit isn't available off the shelf and requires a chahge in the law before it can be used in a civil environment. Oops.
The green machine will be itching to have a pot shot, but a 7.62 long green-spot round will slice through the device and fly out the other side in a parabolic arc for several miles before falling to the ground while still travelling in excess of the speed of sound, which would be jolly unfortunate and slightly deadly for anyone in the way. A shotgun round would suffice with little risk of collateral intrusion into the nearby area, but the footage kve seen shows jt flying well beyond the accurate range of a shotgun. Physically it could be swatted out of the sky easily, but doing so without killing someone near by in such a crowded area is a little harder - a bit like doing precise brain surgery with a lump hammer, sure, it'll do the job ok, but it might make an unintended mess.
Thanks to this joker you can say hello to mandatory registration and pilot licencing, which probably is no bad thing.