Landing simultaneously on 2 elbows or hands, towards the back, is waza-ari for tori and shido for uke.
It is a matter of safety and education for the young judoka who are inspired by our champions.
If uke uses the elbows/hands to avoid the throw he/she will receive a shido.
When we teach ukemi to children, we don't show them to use the elbows/hands to avoid falling, because this is dangerous.
Therefore, it is not ethical to allow competitors to use their elbows/hands in competition; they are role models for our youth.