> the goal is to prevent children from accessing content their parents don't want them to see

This has been mandated in TVs sold in the US. No one sets the thing.

https://en.wikipedia.org/wiki/V-chip

> No one sets the thing.

Based on the surveys from the wikipedia page it appears that 15-20% of parents used the v-chip feature on their TV. For an optional feature that has to be manually configured that seems like an incredible success. I would have guessed that fewer than 20% of users configure any optional setting on their TV.