Apple was sending unencrypted on the network what application you started, if they would "actively tries not to know anything about you" they could have implemented this better.

Anyway how is your assumption make sense , Apple cares about children and about your privacy so scanning your images in iCloud was wrong until 2021 when something changed, what changed? does Apple cares more about children starting from now or they care less about privacy? or are they forced to do it?