[1][2] His songs were popular for their sentimental lyrics that critics said "portrayed individuals' sorrow and frustration at a time when the society was struggling in its early stage of democracy following rapid industrialization.

Kim then returned to school and joined the student activist folk band Noraereul Channeun Saramdeul (노래를 찾는 사람들) in 1987.

Unlike many other entertainers, he earned his fame by singing at concerts along with release of records rather than appearing in TV music show.

He spoke to reporter after getting off to a flying start, "Nevertheless, I'm also afraid that my confidence in the power of songs to affect people's life is growing weaker, as I prosper."

[14][15] A tribute concert has been held annually by singers across musical genres including rock and roll and hip-hop, and his albums sell steadily, marking 5 million copies as of January 2007.

In November 2010, more than twenty artists, designers, and sculptors collectively made a mural to the memory of Kim Kwang-seok in the city of Daegu, where he spent his early years.

Critics and reporters have analyzed his legacy and the persistent fervor for his music in numerous articles and books such as 'Biography of Kim Kwang-seok, an unsent message' by Lee Yoon-ock and 'The 100 masterpiece albums of Korean Popular Music' by Park Joon-hum et al. From the perspective of history of Korean popular music, he is the direct descendant as well as the successor of Korean topical folk rock, which was initiated by Han Dae-su and flourished with songs of Kim Min-ki, Jung Tae-choon, and arguably Cho Dong-jin in early 1970s under the rule of the dictator Park Chung Hee, who was in power from 1961 to 1979.

However, even though Kim Kwang-seok's music was clearly rooted in social issues in his early years of his career, he also empathized with the sorrow and frustration of individuals, which had been downplayed in the struggle for democracy.

Around the late 80s and early 90s, with the improvement of democracy in Korean society, the young generations began to turn their attention from collectivism and community to individualism and experiences of their contemporaries.

Lee Joo-yup, a music critic, argues that his songs portrayed individuals who are constantly wavering on the border of pessimism and optimism, but sublimated the self-consciousness that never gives up the strain of facing reality.