[Twosugars]

I think you paint a somewhat exaggerated picture of that engagement.
I don't know about US, but here not many grownups study family law or real estate taxes before voting. We don't have endless referendums like US has with their state elections.
And re. social media, well, I think that ship has sailed already. Kids spend loads of time on that anyway, they may just as well do something productive with it from time to time.
Also, how young are we talking about? You said kids, I repeated kids. I had 16+ in mind. Here this is the age of consent to sex, they can drive at 17. At the moment they can vote at 18 (some argue it should be lowered to 16).
The days of idealized childhood from the 50s are over. Young people encounter things like environmental issues, immigration etc from an early age.
Besides if we waited for people to be fully mature (emotional maturity) then according to psychologists we'd have to wait until 25.