I assume this clip is spread by the regime for a reason. The reason could be agitation, display of strength (terror), teaching helplessness, or simple clickbait. We can speculate.

We know that in other cases they deliberately choose to release to the public certain info, and withold or manipulate another info.

Since they are distributing it, we are helping them, if we share it among each other. We are doing their job for them.

My guess is terror (display of power) is the purpose. Same type as with videos of SWAT raids, show trials, military exercise etc. It is simple propaganda.