I just found out that the reason he didn't contribute too much for the album was because ge lost his phone containing more than 250 riffs. I found that a little BS but here's what he says:
“Let’s just say it’s like, the reverberations for me, the consequences of losing my cell phone have been immense. I mean, it doesn’t matter who you are or what type of person you are, I think losing your cell phone is traumatic for anyone. And I mean, okay, I lost my phone, I lost a lot of music, but I mean, people lose cell phones, they lose all their personal information, you know? I’m kind of a technological sloth. It took me losing my iPhone to figure out that I can back it up to the iCloud. And the ironic thing about that is, the guy who invented the cloud is my next-door neighbor (laughs).”
And then he talks about the riffs he lost:
“Let me tell you this. I had about, I don’t know, 450 entries in there, which means there were about 250, 300 riffs, because a lot of times I’ll write different versions of the same riff. And when I lost my phone, I could only recall about four riffs. So I’ve closed the book on that (laughs). And, you know, I’m sitting on some music—now!—that I’m happy about. I’m just waiting, waiting for an opportunity, you know, where it can grow.