I am part of the straight audience for whom I expect much of the educational element of the film was aimed. I remember seeing this film sometime after 1978, on TV, when I had just moved to the San Francisco Bay Area. I knew almost nothing about homosexuality at the time.
I remember particularly the young man who said he had never been in love, and then in college suddenly developed a crush on another young man. I had had heterosexual crushes on various people in my teen years, and the lightbulb went on, "oh, THAT'S how it works!" I suddenly realized two things -- that gays couldn't select who they were attracted to any more than I could, and that I didn't want the young man in the documentary to have to live without love in his life. The message was so easy to understand, I was just sorry that the film didn't have wider distribution during the following 30 years.