I have a question for folks. This young man was 17. Most folks in this discussions have said that because he was 17 it’s different as opposed to, say, an adult.

What materially changes when someone goes from 17 to 18? Why would one be okay but not the other?

You have to draw the line somewhere, more or less.

The legal definition of an adulthood doesn't match the biological one. Initially it mostly is a cut off to know if you can be enrolled by force in the war machine or not