There is a YouTube series "Odd One Out" by Jubilee with that premise, not necessarily gay but other social groups as well. In one episode, there really were only Odds and no one how was what they pretended all to be
So when one of them is voted off, does a screen plate report the exiled contestant is gay? Because if they're all typical straights and the comedy is based on them being at least a bit homophobic.
This reminds me of classic USMC gay chicken, which seems to be a conspiracy to turn all our fresh trained marines totally gay questioning.
If all the men are straight, the game will end after one week no matter who gets voted out (and everybody except the one guy who's worst at acting gay gets $1M).
I guess that's not a problem, as long as the folks making it are okay with it being a one-off special and not a series.
The more time that passes between each repost is more time for the premise to be less "2005 dude-bros can't fathom being unmasculine for a second" and more "when did Troye Sivan write this?"
I feel like it would work better as a show with like 5 gay men. That way you get reaction shots of gay men judging straight men trying to act gay, and things actually progress romantically. I feel like anyone who thinks they are the one straight guy might just act like a sexually conservative gay man, the pressure will be on when people start talking about things getting more sexual.