yes, I suspect they're bisexual to a point but Viagra and $ money help them perform as pornstars or escorts with someone they're not attracted to, male or female.
Chi Chi coined the phrase straight-for-pay for gay men who do gay porno.
https://www.urbandictionary.com/define.php?defid=6994380&term=Straight%20for%20Pay
Yes, but most do and now a days with so many women available for straight men getting a bf and keeping him (I'm not even talking about marriage) is an accomplishment.
One thing is two gay men having an open relationship, but a woman dating a guy who is openly bi or in the closet is not that common. I guess women (specially in a big city) must accommodate to whatever they can get and keep. I wouldn't be surprised if this king of arrangements become more common.