I suspect most bi people simply call themselves straight, because their homosexual attractiveness requirement is too high, or they're in denial. Bi-erasure probably doesn't help either.

I think the true number of bisexuals is much higher.

I mean, people still insist on thinking Freddy Mercury was gay, when he was openly bi-sexual.

Its startling because it should be way higher of course! People just won't admit to themselves what they like, what a shame.