The idea of opposing excessive regulation isn't the same thing as this idea that regulation is a sliding scale with "more = worse" and "less = better". But yes, opposition to regulations did exist before. The former isn't a Koch thing, the latter is.

Atlas Shrugged was more the manifestation of the wet dreams of snowflake industrialists who felt intimidated by union power and communism (which were significant in the 50s, hence the rise of the middle class).