Recent descriptions of the science back then also often overstate how generally accepted global cooling and imminent ice ages were. Most of what you hear is ultimately references to an absurdly sensationalist 1975 Newsweek article.

Global warming from carbon dioxide emissions was definitely a widely discussed hypothesis; I recall a review pointing out that there were more 1970s papers on that than on anthropogenic global cooling, but what I know is that the notion of anthropogenic global warming was clearly in the air in popular culture, because the movie Soylent Green (1973) explicitly uses it as background.

What I remember being taught in school was that it was possible that human activity could either warm the earth (with greenhouse gases) or cool it (with smog), but that nobody knew for sure how climate was going to evolve. And later the science became stronger.