Would you correct Navy junior enlisted in dress whites at the airport if you notice them wearing headphones, neck pillows, backpacks, etc.?

I would pick one, take that person to the side, and make it friendly discussion not a butt chewing.
Id make them aware doing what they are doing brings them attention they dont want. Reinforce they are always being looked at as a representative of the service when in uniform

Absolutely, but just talk with them to where it's a 1-on-1 or small-group conversation. No need to embarrass them.

As everybody stated I would talk to them and let them know what the violations are. But rather than embarrassing them I would talk to them on the side professionally. Some times now enlisted service members need a pull up. I know I did.