"Pop" Metal

Pop is ALL about crafting the song (strong hook, clear singing, understandable lyrics). Prog is more about making it interesting musically (odd/changing time signatures, chromatic harmonies, complex lyrical topics). Rarely are bands good at bringing the two together. Also, it's totally normal for pop songs to be in 6/8 or even have the bridge and/or chorus in 6/8 and the rest of the song in 4/4.
 
Zod, I think I understand the point you are trying to make, except for the fact that a good majority of Sonata's songs, however upbeat of a tempo they might have, are about loss of love or other sorts of depressing/sad issues.

That's still the point. The "Pop" reference is attributable to the feel and vibe of the music, not the lyrics. Lyrically many Power Metal songs are about dark subject matter like death, destruction, despair, evil etc. It's not really all about Dragons as the cliché suggests. If "Pop" Metal bashing tr00 metalheads were to read the lyrics of these songs they'd love the words. It doesn't change the fact that the delivery still sounds like cranked up Journey played with speed, double bass, and distorted guitars.