I'm neither a parent nor a teacher. With that caveat:

I wonder exactly how I would (were I a parent) encourage my child to read one thing over another, apart from simply keeping appealing books at home, going to the library, reading kids' books aloud, being visible about the time I spend reading long-form publications and thus modeling that activity, etc. Gradually, reading would become the child's decision, and their decision would be related to other peer and cultural influences.

Perhaps certain teachers are to blame for deprioritizing reading, although I think the emphasis on standardized tests doesn't come directly from teachers but is placed on them by school admins, who are pressured by state regulations that may make school funding dependent on test scores, by colleges that base their acceptances on test scores, and (further down the line) by employers that have their own metrics that very rarely include "ability to read a whole book."