It can be but I don't think it was in this case. Pogacar looks so strong that he could have pulled it all by himself, Sivakov helped but I don't think he was critical. Counter-factual so we will never know.It can be quite significant.
Fwiw, I don't think it was the right decision from Sivakov but if he's looking at it purely for himself then his chances for a medal were 0 without working and 0.01 when working. I get why he did it.