Case in point is Ventoso in PR last year. Nasty looking chainring ‘bite’ (I should know, I have a massive one on my right shin) complete with jagged edges, no riders near him with disc equipped bikes. But no, it’s a disc that causes the injury.
Same with this one. Doull is pressed against the barrier, Kittel (the only rider in the race with disc equipped bikes) is nowhere near him, and on his right hand side. So instead of questioning how it happened (caused by barrier?), it’s an immediate cry of a disc cut.