The only idiot is Sagan. Almost every sprint involved in incidents. Yesterday too. It is an unwritten law that whoever leads the way can choose his own line. As long as he doesn't ride anyone into the barriers. Sagan never got past the rear wheel of Van Aert. Which also left just enough space. The jury knows more about it than you do.
To the right of WVA was the only direction for Sagan to go if he was to have any chance of winning. The path to the left was blocked off.
I don't see the commissars relegating WVA, but if they did, they would be justified.