Hell if I know. I've always been way out of the loop.
But when I found out that heavy-riffing pop-punk bands with death vocals were some of the hottest acts in the commercial sense, bands like Atreyu and such, I figured metal with death vocals would finally break its way into the mainstream sometime soon. Like, the next Metallica would be a heavier band, maybe melodic death or deathcore. But maybe that's already happened with one of those Killswitch Engage ilk bands, I have no clue how popular they are.
But what you heard would make a lot of sense considering how much the record industry is hurting for sales and how many of the people who would normally buy the flavor of the month are now just getting it for free online, whereas a lot of us dudes will download a new album when it leaks but still always go out and buy it when it comes out. Of course you've got to wonder though, even if we're a more dependable fan base, would it still be more profitable than the pop r&b singers and such? When you think about the massive sales that those artist get, I wonder whether any level of dependibility from hardcore underground fans could ever be viable compared to the alternative.