Slides, extensions of the stock that do not fully encircle the barrel, and the receiver (or frame) of a firearm itself are generally not considered barrel shrouds. Barrel shrouds are commonly featured on heavy machine gun barrels, along with a carrying handle, as to better allow the firer to swap barrels.
I see the shrouds have no effectiveness on performance, which could be why I don't recall these having been mentioned before. Probably experienced hunters are familiar with them.
I wonder if the reporter was.
Seems like the large capacity clips are more important.