Democracy is this:

Imagine 10,000 people in a town. I propose a bill to charge everyone $5 per year...The money will be given to my 5 friends. Will the bill pass?

Yes. It will pass every time. Why would anyone vote for it? Simple because my 5 friends are incentived to go muster support for this bill....they will go advocate for it, create plausible sounding arguments why its needed, maybe some of them will pay some of their friends to vote yes, etc...

Meanwhile its not worth the general publics time to advocate against it. The $5 tax doesn't rise to the level of being "actionable" - its basically something just to ignore.

Hence why these bills always pass....and after a couple of decades of these the frog is slowly boiled.

The goal of lowering voting age to 16 is to increase the pool of voters that are easily swayed by my 5 buddies arguments. They know 16 y/o will respond to simplistic moralistic good-bad tropes....thus we can keep our scheme going.