According to Obermann and confirmed by Wiki, Glenn Burke, Dodgers & Oakland, April 76 to June 79, was the first out MLB player. By 1978. everyone knew, including sports writers, as Burke was very open about his life to everybody.
According to Obermann, Burke later said, "Everyone just pretended not to hear me [when I talked about being gay]." I guess they were a lot like my Moma.
Somebody else has probably posted about this before but it's news to me. Given the state of my brain, I'll probably post this again next year. Every day is a new day.