I don't consider myself old... or even much of an adult, but I feel like i've long outgrown concerts. It seems like all I read about is fans getting seriously injured and crowds of people too preoccupied video-recording instead actually enjoying the music.
Stop reading about concerts and start going to them. I just saw Lacuna Coil last night and had a blast. Most people weren't on their phones either, save for during one song by the supporting band (New Year's Day) where the singer specifically requested that everyone record it.
Who cares if people are on their phone? I'm watching the show. You do you.
I don't understand why it matters. Some artists even lose their shit if people are on their phone. Like dude, they fucking PAID for the show. If they wanna miss it, that's on them. Such a weird thing to care about and waste energy on.