This is a pet topic of mine. Here are some interesting breadcrumbs, although a sister post by dv_dt above was a far better summary than I could give, there are some things I think are illuminating specifically. While not specifically from the presidents you mention, I ascribe to a theory that there were broad cultural and economic shifts that caused the results you see.

- The Powell Memo in 1971 [0]

- Rise of corporate raiding ~1980 [1]

- CPI inflection in 1970s [2]

[0] https://en.wikipedia.org/wiki/Lewis_F._Powell_Jr.#Powell_Mem...

[1]https://en.wikipedia.org/wiki/Corporate_raid

[2]https://en.wikipedia.org/wiki/Consumer_price_index#/media/Fi...