Two male bunnies aren't IMPOSSIBLE to bond, but it's not a very easy bond either. Generally it's recommended to try male/female neutered as those are the easiest. I've had more female/female pairs than male/male pairs, for what it's worth.
We are as gods to the beasts of the fields. We order the time o' their birth and the time o' their death. Between times, we ha' a duty. - Terry Pratchett.
"Men have forgotten this truth", said the fox, "But you must not forget it. You become responsible, forever, for what you have tamed. - Antoine de Saint-Exupéry