AUS-8 is hardly low carbon steel. It is a high carbon stainless and can be hardened to about 60 HRc and even higher. As was said, heat treatment determines this. I don't know how hard CS makes their blades, but it's not for lack of ability of the steel. AUS-8 is not low quality. It's just as clean as other Japanese steels like VG-1, VG-10, ZDP-189, etc. Saying it's low quality implies there is something wrong with how the steel is made. The elements in it are the ones intended to be there in the desired quantities. I have tried some of the above steels and AUS-8 has some desireable properties even compared to this group of steels.
BTW, how can a newer steel have been on the market for decades?
AUS8 is .7% carbon, pretty low compared to most of the new stuff. Buck still calls it's 420 high carbon SS, Sandvik 12c27 is refered to as high carbon SS....at one time they all were.
I worded that pretty piss poor....newer meaning the D2, 154CM, ATS-34, etc. not the CPM stuff that is just flooding the market.
How about this...."AUS8 is good quality, for a cheap, outdated, low carbon by todays standards SS, and is commonly found in many production companies low end knife lines"