However people are influenced by cultural archetypes even without thinking about it. Just from subconscious mimicry or a person's expectations a person may end up with a certain sounding voice, certain mannerisms,...You name it. When a group of people is oppressed this may even lead to conscious pushing for these changes as identity and then backlash from people who see this as conformist and then new identities arising from that (bear) which can lead to new stereotypes and then identities that form trying to avoid or affirm those.
It's the same way any identity works.
It's no brainer that the mannerisms, accents and sometimes habits of parents be mimicked by children. I've seen it all the time even as a child I knew this. It's common sense. The "acting gay" mannerism is usually when a man adopts the mannerisms of a woman. Boys that play with girls in an early age sometimes have this symptom.
In my view, it would be possible to seem like you are "gay" to others (as interpretation is left to individual opinion) but would not necessarily BE gay. Stereotypes are large-scale generalisations which are cast onto people by a dominant group. The dominant group usually reflects a sort of cultural expectation which categorises people into either or situations (in other words, there is no room for grey, it's simply a case of black or white). The common fault with generalisations (based on the way we interpret people's behaviour and actions) is that if we say that someone is gay simply because they act "gay", then that person indirectly attributes himself or herself as actually being gay because of what they are told (programmed to think) by the dominant group.
This is a pretty offensive question. What is "acting gay" exactly, prancing around with your wrists limp? People don't "act straight" or "act gay" outside of when they're having feelings or relations towards the gender that they're interested in. All gay people don't act the same, people can't "act gay" as heterosexuals unless they're trying to overplay some stereotype like the one listed above.
How on earth do you act a sexual orientation? How does one act gay? I myself am gay, is there some sort of "gay agenda" memo I missed? What constitutes as "acting gay?" Is this a new emotion? Is it an iOS update for humans? Honestly folks, how in the world can you possibly act a sexual orientation? This question is offensive and a complete waste.