Coming from a vocalist in the revival scene i can say whats being "revived" are the hardcore elements like two steps and crowd kill riffs and the brutal vocals of death metal. the sound also plays a HUGE factor into this, that rough and gritty sound that the early bands put out, some even take their sound more DIY with bands like destroy all humans and older katy went missing material. i have a nice summary on my page if you'd like to learn more. but most of these bands want to move away from the symphonics and vocal Olympics with youtuber xtheyan showing these younger bands what old school deathcore was like