The four justices who disagreed with the ruling did not do it on moral grounds. It was based on the fact that they thought the supreme court had no business pushing through something that should be decided by the people and the states. To quote Roberts: the dissent is about “whether, in our democratic republic, that decision should rest with the people acting through their elected representatives, or with five lawyers who happen to hold commissions authorizing them to resolve legal disputes according to law.”
Or as Scalia wrote: “States are free to adopt whatever laws they like, even those that offend the esteemed Justices’ ‘reasoned judgment'”.
They view this as a gross overreach of power by the supreme court and fear that once you limit the constitution’s power you can slip very quickly into what this country was founded to protect against – abuse of power by the leaders.