This is what bothers me a lot about all of this.
The pretending that we don't notice these things.
I am totally on with not commenting in personal interactions on people's appearances. Though even there I think we have crossed the line into an unhealthy avoidance. But I am not going to comment on someone being really fat in a normal personal interaction.
That is a totally different thing than describing people unknown to the audience in writing. I can't get over this idea for example that by noticing a student had a very sexualized appearance, somehow it was Clanchy that was sexualizing her and therefore putting her in danger. As if all the other students, and adults including ones who are not looking out for the student's interest, weren't perfectly able to recognize that on their own. And also as if that kind of observation is of no interest to the reader - of course it can be, because it tells us a lot about that student's situation, what some of her struggles might be, what fangers face her.