Says the guy with his tail between his legs, giving us another excuse why you're fleeing.
Your argument doesn't work. Marriage has already changed. Women are equals in a marriage...which they haven't been in the past. We don't have polygamy, despite polygamy being quite prevenalt in the last 2000 years of human experience'. We don't have interracial or inter-religious bans, despite those being preveleant in the past.
And we no longer kill gays the way the founders did. But instead, recognize they have the same rights and freedoms as anyone else. Why then wouldn't they have the right to marriage, which all straights already have?
And remember, I've already got your number with your whole 'they can marry someone of the opposite sex' schtick. The restrictions on marriage must themselves be constitutional, as Loving demonstrates. And contrary to your silly opinion, race based discrimination cases are relevant. As demonstrated by the USSC which has already cited them 4 times.
The USSC is a far better source on which USSC cases are relevant than you are.