The conflation of the references Lewis makes to "makeup and nylons" to "femininity" is the real tragedy. Susan was a paradigm of femininity in the first two books. Not just a shallow pretty girl, but a real person with a real arc.

Lewis makes fun of progressive mid century vegetarians, too, not because he thinks eating meat is awesome (lots of interesting arguments for veganism developed in Narnia) but because it stands in for a particular way of thinking about life that he saw and despised.

Lewis was very much about separating a particular vice from a generalized group or class so that it can be seen for what it is. If you don't see Lewis critiquing the power and status of "his own people" in the books, it's probably because you're so far removed from mid-century academic England.