Hegarty argues noise music only becomes a genre proper with 1990s Japanese noise

Since the early 1980s, Japan produced a substantial output of harsh noise — the Japanoise scene. Paul Hegarty (2007) argued that noise music only makes sense as a genre with the vast growth of Japanese noise in the 1990s. Key artists include Merzbow (Masami Akita), who took Metal Machine Music as a departure point but freed the noise aesthetic from guitar-based feedback alone, abstracting it further. Others: Hijokaidan, Boredoms, C.C.C.C., Incapacitants, KK Null, Masonna, Solmania, K2, the Gerogerigegege, and Hanatarash. Merzbow’s name derives from Kurt Schwitters’s Merz collage project. Nick Cain of The Wire identifies the primacy of Japanese noise artists as one of the major developments in noise since 1990.

Examples

Merzbow’s prolific output (100+ releases); Hanatarash’s extreme performance art; Hijokaidan’s live feedback performances. Merzbow’s alias comes from Dada artist Kurt Schwitters’s Merz collage project.

Assessment

Why does Paul Hegarty argue noise music only becomes a ‘genre’ in the 1990s? What quantitative and qualitative contribution grounds that claim?