Considering stuff like that's been going on since the Civil Rights Act of 1964, it's a pretty long-lived fad. Or do you just mean the more recent adamant support of gay/trans rights are just a fad?
Things "going on" is not the same as widespread social acceptance. Even in the 80s, being gay was not something you would advertise. Whereas in recent years I've actually spoken with teenagers who have bragged to me that they're bisexual...but then when I ask them what it's like to take cock they get confused because "eww that's gross."
Because it didn't occur to them that being bi-SEX-ual would sort of imply that one has sex with both genders, and most likely they were simply making the claim because apparently it's "cool" now.
Yes, there have been civil rights activities for quite some time, but from my point of view those activities have overextended their target, and gays are now a socially protected class. For example, if a girl says "I don't like short guys." People who aren't short guys will generally be ok with that. If a person says "yeah, christians really annoy me" people who are not christian will generally be ok with that too.
...but say "I don't like gays" and a large percentage of people who are
not gay will immediately attack you for it.
To the gay community, I acknowledge that some of you have had to deal with a lot of unjustified misery. However, I would offer you the advice that pendulums tend to swing. I think it would better for both you and everyone else if your sexual preferences were a thing of casual indifference to people rather than something they feel they need to protect.