I've been with plenty of couples. Some with openly bi males nd some that were hiding it or confused about their sexuality and how to broach it. And of course, some with straight males, and that's a mixed bag because some want no male to male touching of any kind and others like to guide my cock into their wife or partner's pussy or taste the juices off of my cock afterwards. And that's all fine with me. I view myself as an occasional extra in an established act and I try to add what I can to that dynamic while I'm apart of it. But I've definitely found that having a bi male who is open about is makes things easier, less complicated and naturally more fun due to the extra combinations of things you can do together. I get turned on knowing that the wife is turned on watching her man suck my cock or getting fucked. It's specially nice when they suck and /or rim me together.
Then again, I can understand why some guys would be hesitant to open up about it with their partner- it can be a make or break thing in some relationships. And no males are still looked down on by a significant number of eople in modern society. Definitely nowhere near the acceptance levels of bi females. I myself am a bi top but I don't always feel in the mood for m2m play (almost always though lol) and I don't advertise myself as bi in my personal life or on the site because of those reasons. Some couples and even some single women are put off amd want nothing to do with me if they know I'm bi so I tend to be discreet about it until I gauge how they feel about it. And it's not like its a pre-requisite that I'll want m2m contact but alot of straight guys think I'll wamt to touch their dick and they are scared of how they'll feel and what that'll say about them. I can play straight or no depending on the situation and genuinely enjoy both but neither are absolutes in my mind.