No amount of "this is not the purpose of a standup" and "you're doing it wrong" can fix human nature. Management is mostly interested in progress and timelines, and will give unintentional (or not) feedback, even through body language, whenever a task is delayed or impacted in any way. They have some authority over team members' performance eval. Hence people will end up reporting to them no matter how hard you try. The only possible fix is to remove management or product from the standup, which is how it was originally supposed to be - but that seems unthinkable in the "agile at scale' format most companies have adopted today.
