"Political activist" being the politest way to describe him.
http://www.nintendoworldreport.com/news/58604/koichi-sugiyama-japanese-political-activist-and-dragon-quest-composer-dead-at-90
One of Japan's most infamous composers and a pillar of the Dragon Quest series has died.
A statement from Square Enix announced that Koichi Sugiyama, who composed the music and sound effects for the Dragon Quest series dating back to the 1986 original, died on September 30, 2021. The cause of death was septic shock, a sudden loss of blood pressure following an infection.
A veteran composer, Sugiyama was known more for his extreme nationalism in recent years, including being a signatory to a full-page letter published in the Washington Post denying an apology for Japan's use of "comfort women" during the Second World War. He was also a noted denier of the Nanjing Massacre, and dismissed the high suicide rates among Japanese LGBT+ youth in 2015.