This band writes giant mecha theme songs.
It's what they do.
they've been making anime worthy songs forever (between breaking up like 3 times)
Dir en grey (no, sticking "child prey" on the US version of Grappler Baki doesn't count)
Versailles (I think they even covered the Rose of Versailles theme)
it makes NO SENSE that this band hasn't had an anime OP. . at all.
I didn't even go as far as mentioning non-Japanese bands, but I'm sure you can think of a ton.
IT SHOULD'VE BEEN YOKO!