If this were to take effect with the bulk of social life taking place digitally we can expect minimum voting ages to be decreased the same and in the case of the US, the age of consent for sex to be standardized in the same direction too with a deemphasis on 18 as the de facto minimum at the cultural level.
And we can expect 15 year olds to hit the workforce full-time around then too I reckon. Or younger. Imagine 9 year olds stowed away in Waymo taxi trunks with socket wrenches and cyberdecks.
Or we could stagger the introduction to adult society, like we do today.
Drinking beer at 16, drinking liquor at 18 for example.