Except when Juniors are humble and like "yes sir yes sir", don't defend their design assuming seniors know more and internalize everything. And except when seniors give conflicting feedback based on what they read yesterday. It was mostly impact on those juniors I found bad. They were told their code is crappier then it really was and lost a lot of confidence. They started humble and ended afraid to do anything except simplest tasks.

Also, they got only and exclusively negative feedback. Instead of being told in advance how to do things where we are opinionated or being encouraged to ask questions or just being led/given hints, they were expected to do it alone. Then they were told they done it badly and were effectively dictated how to rewrite it.

Tech is not different from anything else - teaching people should involve more then just telling them they suck. It should involve telling them what they are expected to do in advance.