Is it? There is still a huge market for this kind of music. SWS did around 60k last year. To me it just seems like for whatever reason, Chiodos just hasn't been able to maintain their popularity into the new decade.
The reason is the amount of time that passed between BPB and a new album with Craig at vocals imo. Devil killed DRUGS and Illuminaudio sales numbers though. So the 18K is still damn impressive in my book.
You are correct this type of music still has a market. But sales numbers for all music are down from 2007. That's why I said it is unfair to compare them.