Good parenting solves these personality trait concerns without a foot in the door for mandatory suspension-of-disbelief busting watermarking in all ai output. Adults have the right to regard any human (or non-human) effort in any sphere at whatever level they want, for whatever reason. They don't need to be reminded of it every interaction forever more as punishment for voice actors losing jobs in 2023 and to lighten the load on parents.
I get that children can't distinguish personhood well and might grow up disrespectful of real humans if left to AI but the same argument applies if left watching youtube all day. There are new expectations on all of us to compete with new tech. We can manage without knee jerk nanny state style encroachments at every turn.