In 1977 Australia men were already wearing a string bikini per a televised ABC news report. Macy's stores actually sold a version of this style (see link below) in both the Los Angeles and San Francisco Bay areas during the early and mid 1980's, having it displayed on a few store male mannequins.
My first wearing of this style in public was during the summer of 1982. Spent an entire day at the Santa Cruz Boardwalk and beach wearing it accompanied by my wife with nothing, but compliments. This is the minimalistic, but still full coverage Speedo style that I still wear.
https://youtu.be/4Px7QJ8j1e0