I think there is definitely something to the idea that being in a same-sex relationship challenges norms and fosters good communication because more things have to be discussed openly rather than just copied. On the other hand, same-sex relationships can be fraught with problems like any other relationships are.
But we certainly aren’t LESS likely to be happy. Nor are the children we raise. That’s not even an open question anymore, as far as people who use empirical data are concerned.
Thanks for your excellent point. :-)