Hi just in passing - I notice that the source cited for "progressive metal" just lists their styles as alternative thrash and speed metal... Just randomly mentioned progressive metal in the piece of writing about them. 
Not to seem nasty or anything but symphony x, dream theater and similar are progressive metal. They bare much fewer similarities to trivium than say metallica, sodom or other thrash bands do. Even if we don't call them metalcore anymore, they have plenty of similarities to metalcore bands still.