I don't think the point is to be found in one's sexual orientation. The thing is the rainbow emoji can communicate much more than that due to how it's used by conservatives, unfortunately. Some people may turn your application down simply because you have a rainbow emoji in your bio and they've heard conservative bullshit about some inexistent LGBTQ+ lobby that wants to chemically castrate every single child on this planet.
Yeah, I gotta agree with the other poster here. If the person is interpreting "rainbow emoji" as a signal for "gay people bad", that seems like a company you definitely wouldn't want to work for, considering they _wouldn't recognize your basic humanity_.
What's most wild to me is that here, on hackernews, people are saying "Don't give _any signal_ that you're gay", and making that seem comparable to other actual controversial things on your profile.
People are dumb. Better be safe than sorry.