It is hard to know how to answer this question because there are very many different categories in which the United States has or has not made progress since the mid-1970s. If there is a specific area of life that you want addressed, please let us know. In addition, it is hard to answer this because there is, in many cases, no objective way in which to define “progress.”
For example, it is possible to argue that the United States has made economic progress in the past 40 years. Real GDP per capita has almost doubled since the mid-1970s. However, many people would argue that we have actually regressed economically since that time. There are fewer good jobs for people without college degrees. Income inequality has risen. It is hard to say if we have progressed.
As another example, we can look at the degree of justice and social cohesion that we have today compared to 40 years ago. There is surely less racism and sexism than there was back then. Gay people are much more accepted today. This seems like progress. On the other hand, our rates of marriage have dropped. We have many more babies being born to unwed mothers. These do not seem like progress.
Overall, then, progress is very much in the eye of the beholder. I would tend to argue that we have progressed since we generally have higher standards of living and less injustice than we had then. But there are those who would dispute this assessment.