It was still a constant fight but, union membership was at 23.3%, annual strikes and work stoppages were measured in hundreds, wages increased proportionally to productivity gained through technology, and executive salaries were 5-10x average workers'.
Reagan, who had benefitted from membership in the Screen Actors Guild, launched a political war against unions and labor rights, starting with the firing of 11k striking air traffic controllers who he banned from working for the Federal government (a ban only lifted in 1993) and dissolved their union (a fun sidenote to this being that PATCO were the only union that endorsed Reagan and a final "fuck you" cherry on top was the renaming of the DC airport to Reagan National). This showed business that, at least under a GOP government, strikebreaking was again allowed.
All that precipitated rapid decline in union membership for workers in the US, leading to a cycle of increased share of wealth to the top, which was used to buy more legislation to erode labor's power and roll back protections, which increased the share of wealth to the top...ad infinitum. Now, union membership is 11.3%, exec pay is 400x that of workers, and compensation has completely decoupled from productivity and stagnated.