I don't think there's anything wrong with looking other places to learn and grow as a guitar player, musician...and music listener. I hate modern metal...talk about "posers". Half the time Godsmack and all the other copycats (of whoever) are talking about being upset with the girlfriend.
I still have a fondness for good 80's metal (not Poison...but Helloween, TNT, Maiden, Raven...etc), but I have also grown into jazz, fusion, the jam band scene (like Moe/Umphrey's/etc). All part of my musical journey that I wouldn't have if I subscribed to your philosophy.
"real music"? I don't think you know.
Adding other interests isn't the same as "growing out of it".
Douche.