If that's not from the majority opinion, how much does it actually matter?

Thomas wasn't part of the majority? He wrote a concurring opinion - he agrees with the main decision and went out of his way to further explain his thoughts, including that he disagrees with any of the rights created under the auspices of due process. But, he conveniently left Loving v Virginia off the list, which was also decided (partially) on due process grounds - I guess he's not quite so sure about his principles that he'd blow up his own marriage.

He also lives in DC, so even if he did rule that the states have the right to criminalize interracial marriages, HIS is unlikely to be affected.

Nope, he and Ginny live in VA.

quite a bit, the votes are likely there to overturn those things as well.

what thomas did is a little gauche, the court generally avoids opining on cases that aren't actually in front of them because the facts and specifics of the case matter, but, yeah, the votes are probably there, thomas just likes to say the quiet part out loud.

who do you think is going to vote against it? thomas, who has outright stated he's a yes? kavanaugh, who said roe was "settled law"? Barrett, the actual handmaiden cultist? Alito?

I think, realistically, we're holding out for Gorsuch and Roberts to not be monsters, and I think we will be disappointed.