Did the upheavals of the 1970s strengthen or weaken democracy in America?

Since you don't mention any specific upheavals in your question, we'll look at some of the most significant upheavals of the decade of the 1970s and how they affected democracy in America. These included the Vietnam War, the Watergate scandal, and the struggle for women's rights.
The United States had been involved in the Vietnam conflict for decades, and by the late 1960s, the situation had escalated to the point that more than 500,000 American soldiers were on the ground in Vietnam. Although President Nixon announced a policy of Vietnamization, which involved reducing the number of American troops in Vietnam, in early 1970, he expanded the war into Cambodia, hoping to eliminate North Vietnamese supply bases. This prompted nationwide protests on college campuses. On May 4, 1970, during one such demonstration on the campus of Kent State University in Ohio, four unarmed student protesters were shot and killed by National Guardsmen.
Protests against the war polarized the American people. The war lingered on until 1973, when the last American troops withdrew in ignominious disgrace. The upheaval of the Vietnam War definitely did not strengthen American democracy. The United States spent more than $120 billion dollars on the conflict, and this spending led to widespread inflation. Even worse, almost 60,000 American men and women died during the Vietnam War. The myth of American invincibility was shattered, and the nation remained deeply divided about the war and its legacy.
In June 1972, five burglars were caught attempting to break into the Democratic Headquarters at the Watergate Hotel in Washington, D.C. The burglars were connected to President Nixon's reelection campaign, and eventually the investigation led all the way backto Nixon himself. At first, he tried to cover up his involvement, but when his duplicity became clear, the House of Representatives voted to impeach Nixon, and he resigned in disgrace. Vice President Gerald Ford became president, and he pardoned Nixon of all offenses committed while in office. The Watergate scandal, Nixon's cover-up, his impeachment, and the pardon by Ford all weakened democracy in America, as they created an atmosphere of suspicion and distrust of the federal government.
Women had been fighting for decades for equal rights with men, and in 1972, it seemed that victory was in sight when Congress passed the Equal Rights Amendment to the Constitution. This stated: "Equality of rights under the law shall not be denied or abridged by the United States or by any state on account of sex." However, when it came to ratification of the amendment by the states, conservative activists created an enormous upheaval in the media as they campaigned against it. Ultimately, these activists prevented the amendment from passing, which surely weakened democracy in the United States, as this denied equality to all female citizens.
https://www.history.com/topics/1970s/1970s-1

https://www.history.com/topics/1970s/watergate

https://www.history.com/topics/vietnam-war/vietnam-war-history