Thing is, the leaders in the sexual anarchy/homosexualist/polyamorist/etc. movement for government recognition desperately WANT the government to give approval so they can use the state to punish those who disagree or disapprove. That is most definitely NOT a “live and let live” kind of ideology or lifestyle.
Which is exactly why conservatives have to get government out of the business of defining “marriage” at all. The only way to win is not to play at all.