After considering recent literature reviews of peer-reviewed studies, my understanding that the consensus of the best scientific findings available regarding sexual orientation is that it is a combination of attraction and behavior, and is biologically-based with psychological next-order correspondences, stimuli, and effects, has been reinforced.
This does not mean much regarding a specific biblically-prohibited act (whose definition, I would note, is subject to the formulation of a national court). But regarding the associated rabbinic prohibitions, this may mean that a gay man may be exempt from those which cause him distress due to their conflict with his specific biological and psychological needs.
In this way (and I hope this is not inadvertently offensive to my gay friends – if it is, I will re-evaluate the approach), a gay Jewish man may find himself in a legal situation akin to that of an istanis, the most famous case of which is Rabban Gamliel himself, who exempted himself from rabbinic prohibitions related to mourning due to their conflict with his biological-psychological needs.
I hope to flesh this out with a more thorough treatment of the classical sources regarding both the rabbinic prohibitions relevant to gay men and the legal definition, concept, and status of the istanis, but I just wanted to share some thoughts that have coalesced in the wake of several conversations that ensued from my post about gay rabbis (which itself was only brought about by the divine providence of two things being juxtaposed in my experience last week).