DOMA ""is unconstitutional as a deprivation of the equal liberty of persons that is protected by the Fifth Amendment... DOMA singles out a class of persons deemed by a State entitled to recognition and protection to enhance their own liberty... The opinion and its holding are confined to those lawful marriages."

Parsed: Marriage is a condition of "enhanced liberty" that a state may or may not decide to give to whoever they want. Whenever they decide to "enhance" someone's liberty, the feds can't roll it back.

That's what the DOMA decision stands for. That "enhanced liberty" language fairly screams "THIS IS WHAT IT TOOK TO GET KENNEDY ON BOARD," so you can see what a future decision squarely on the question of "can a State privilege some citizens with marriage and deny it to others for basically any reason?" is going to be "yep, States can do that - it's totally their call, and there is no fundamental constitutional right for ANY kind of marriage."

You got the latter part right, marriage isn't a fundamental right. But even rights that are not fundamental cannot be denied by the government because of animus or as Kennedy put it to "disparage and injure" some at the expense of others.

So, no, the state cannot deny some citizens the right to marry for *any* reason. Depending who those people are, the government would have to meet various thresholds to deny them a right to marry.