Trivialize the nature of intimate life?

[Cooliegirly]

"It is not possible for a child--any child--ever to use his family's language in school. Not to understand this is to misunderstand the public uses of schooling and to trivialize the nature of intimate life--a family's 'language'."

What does the second sentence mean? Does it mean "if you don't understand this, you are then misunderstanding the public uses of schooling?" Also, how can speaking the family's language (which, in this case, is different than the official language of the society at large) trivialize the nature of intimate life?