Nixon's pardon WAS an issue of accountability to most of the country and contributed to Ford's loss of the election.
Ford's first press secretary and close friend Jerald terHorst resigned his post in protest after the pardon.
The Nixon pardon was a pivotal moment in the Ford presidency. Historians believe that the controversy was one of the major reasons that Ford lost the election in 1976, and Ford agreed with that observation.[7] In an editorial at the time, The New York Times stated that the Nixon pardon was a "profoundly unwise, divisive, and unjust act" that in a stroke had destroyed the new president's "credibility as a man of judgment, candor, and competence".
Destruction of those character qualities of course will not ensue for the prosecution of one who doesn't have them to begin with.
Nixon didn't make it an issue because even HE knew how idiotic and unconstitutional it was. Only the idiot trump, is trying to get out of his treason trial by throwing a sick and demented hail Mary of unlimited presidential immunity which exists absolutely nowhere in the constitution.