The time period I bolded above was the period of the big swing back toward conservative--read evangelical Christian--values. It was also the time of the reaction/blowback (no pun intended) to the sexual revolution, the incredible fear of HIV/AIDS (I can still remember the 1981 Newsweek and Time magazine articles announcing "GRID," Gay-Related Immune Deficiency, which had just been noted as an epidemic in NYC hospitals), the connection of AIDS with what many conservatives saw as "undesirable" population elements (including gay men, prostitutes, drug users, and Haitians), increased book banning, decreased sex education in the schools, and Reagan's "morning in America."
Basically, many people wanted to go back to the 1950s as though the civil rights movement, feminism, the sexual revolution, and the LGBTQ rights movements had never happened. (By the way, this feeling is still strong within modern conservatism, in case those of you reading this post hadn't been paying attention.)
Ironically, the locker-room and shower-room feeling transformed in those few years (the early to mid-1980s) from "real men get naked together, thus showing that they aren't gay" to "there must be some gay guys in here with the rest of us, so let's start covering up" to "enjoying getting naked together must be gay, since gay guys like seeing other guys naked."
NCbear (who remembers showering with Boy Scout leaders at camp as a pre-teen and early teen; whose gym showers in high school, 1983-1987, merely collected dust; whose gym showers and swimming pool showers at college and in both graduate programs were all open; and whose YMCA has retrofitted Formica-covered stalls surrounding each wall-mounted showerhead in a large room that obviously was once an open shower room)