Quite a few recent Duncan’s are signature or quasi signature, right? While Lotta Love, Hendrix, Bead Paisley x2, Joe Bonamassa, Wes Hauch, Angus Young, kind of the Saturday Night Special...
I’d also imagine that it’s like overdrive pedals, the bases are already covered, without an artist pushing this tweak or that modification it’s tough to get traction against the JB/Super Distortion, etc.