For those interested in detailed distinctions between systems approach, systems thinking, General Systems Theory, system science, etc, Aleksandra A. Nikiforova (Lomonosov Moscow State University) started an entry in the Encyclopedia of Knowledge Organization in 2022 that has been revised to 2024.
https://www.isko.org/cyclo/systems .

The International Society for Knowledge Organization is a “scholarly society devoted to the theory and practice of knowledge organization, bringing together professionals from different disciplines such as information science, philosophy, linguistics, and computer science, as well as special domains such as health informatics".