That's what the suggestion list is for. If a band has merits, you can make their case there. We're not trying to die on any hill just because a decision was made at some point in time.
@John doe: Idk who you're referring to exactly, but as far as I understand it, we feature artists who have some something that qualifies as metal, even if it's just a one-off. More rarely so if they haven't, though.