I think the overthrow was initiated with the 1964 Civil Rights Act as implemented, contrary to the statutory language in the law, by the EEOC bureaucracy.  Congress explicitly prohibited racial quotas, but the EEOC under the leadership of Alfred Blumrosen put in place a regulatory system that, at first, under the name of "affirmative action" gave racial preference to blacks in university admissions, hiring, and promotion. Soon after the preferences were extended to women, and later to the handicapped and now to sexual perverts.  

The consequence of Alfred Blumrosen is that white heterosexual males are second class citizens in law.  They have been denied for a half century the 14th Amendment's protection of equality under the law.

Initially, the impact was limited, but as time passed more and more American men were held back in order to advance those with racial and gender preferences.  Feminists went on and on about a "glass ceiling," and American men, weakened by their demonization, invited them on boards and into executive offices.  This has gone on for so many decades that today a male CEO or University president is an endangered species, as exemplified by the recent controversy over Ivy League students' protests against Israel's genocide of the Palestinians.  The three Ivy League university presidents called before Congress to explain why they had allowed students to commit anti-semitism by protesting Israel's massacre of Palestinians were all women, with the President of Harvard being a black woman with plagiarism problems.

Today many corporate boards are more concerned about whether they have enough women and blacks than they are with profits and the corporation's future.

Having pushed men aside, they started on boys.  Boys could no longer be Boy Scouts.  They had to take in girls or it was ruled discrimination against females.  But Girl Scouts didn't have to take in boys.

Boy's Little League baseball had to take in girls or it was discrimination.

Next school playground fights between a bully and one not content to be bullied, were no longer left to completion by the playground monitor–standing up for yourself was regarded as part of growing up.  Today the police are called, and what was normal in my day has been criminalized.  Boys cannot even play cops and robbers or cowboys and Indians without severe punishment.  If a 6 year old points his finger and says bang-bang, the cops are called, and parents are told that their son is a sociopath who is dangerous to his classmates.