Actually both Metallica and Megadeath have both had new CD's in 2016, Anthrax is in the middle of a revamp and putting out a new CD soon. I am also sure if you think about it Metallica took alot of flack for expanding their vision years ago and introducing the 1st metal with a full orchestra.
I do get it though, many of Megadeaths cd's all sound very similar but they also cater to a group that know what they like and Megadeath provides it in spades.
Personally, for me and trust me I listen to pretty much everything aside from like Sinatra(had on Enya this morning and switched to Lenny Kravitz this afternoon, then listened to some Nickleback in the car on the way home). For me I like knowing what to expect when I listen to a bands new music, changing it up radically kinda feels like betrayal since it is the consumers that support the artists.
Alot of the new music(not all) I can't get behind. The voices are so synthesized that you can't even tell some of them apart. I have a terrible time with Sia, Rhianna and this other lady. Do I like where the music industry is headed? Not really, I want artists with great and unique voices to really showcase their talent unaccompanied. Lately, that is just not happening much unless you look to older bands. A bit depressing TBH and that is my personal opinion since you took it opon yourself to assert yours.
RANDOM FACT Do you know that James Hatfield was not the original singer for Metallica? Nope, Dave Mustaine was. There was a issue between Dave and the rest of the band and he was fired. They then picked up James Hatfield and have what we now know as Metallica. For those who are not familiar, Dave Mustaine is the singer for Megadeath so when he was fired he made the lateral move. So there you go. I have met Dave in person but while cool, the back stage area is kinda crazy and I am pretty sure he wanted to get back to the twins that were "there" for him in a special booth..