Earlier quoted context omitted.
I believe that is an extreme and cartoonish conclusion to draw from so little information. How do you know that is the experience the children have? The sister comment from another teacher brings facts to the table that explain the intent of the exercise, which is limited in scope and aimed for a specific purpose. Good or bad it is a game to attempt to teach kids it is ok to admit they don't know and to ask for help…
I have enough information to tell that children in this case are forbidden to ask their question unless everyone in the group has the same question, because that information was explicitly given. This is not the same rule as one which allows an individual child to freely ask the teacher whatever he likes, whether his groupmates want to ask or not, if he still feels like asking after trying his peers first. The former…
Hell, it could be an exercise to teach students the dangers of group think. It would be intellectually dishonest of the author to frame the situation in the way that she did, but we have no idea of the context. Did the author watch the whole class and speak with the teach afterward, or did she just observe the class for a few minutes?
Without more context you just don't have enough information to make such a damning judgement.