I was a social studies teacher for 20 years before getting into administration, and I've been in that for 17 years. I've seen social studies objectives removed from high school graduation requirements and the number of social studies credits required for graduation reduced. Common core, and its emphasis on technical education, science and mathematics core objectives, is the culprit. Prior to its implementation, American high school students had to pass four social studies courses to graduate, including a full unit of American History, a full unit of Government/Constitution and an exam, and a full unit of Economics. And the curriculum is nowhere near as rigorous as it was when I started teaching in the fall of 1979.
Common core placed the emphasis on technological education ,math and science objectives, as a result of American student achievement in those areas being well below the developed world. The reading core objectives are aimed at technical reading, not interpretation or critical thinking.
But, I've only been in the field for 40 years. And I've seen everything here, if you want to bother yourself with facts.
https://edsource.org/2023/latest-test-results-underscore-declining-knowledge-of-u-s-history-and-civics/689766#:~:text=May%203%2C%202023&text=Only%2013%25%20of%20students%20scored,decline%20from%2034%25%20in%202018.
https://www.edweek.org/teaching-learning/understanding-the-sharp-drop-in-history-and-civics-naep-scores-4-things-to-know/2023/05
https://www.rand.org/pubs/commentary/2023/05/social-studies-achievement-has-plummeted-nationally.html
https://www.smartstarteducation.com/eighth-grade-history-scores-on-the-decline-2/
https://www.washingtonpost.com/education/2023/05/03/civics-history-education-naep-democracy/
13% proficiency in American History, and you want to tell me that doesn't affect the way people vote? 
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