We're constantly digging up old and dead things because we care.

But they stay dead and we can study them at our leisure. If it was people who started walking around again doing stuff, we'd have a different opinion.

You really think if we could reanimate some ancient person, we wouldn't? Imagine what we could learn from important people in those times.

It depends. If cryonics becomes widespread, "ancient people" in suspended animation would be pretty common. There wouldn't be that much to learn from reviving all of them.

One would hope that the rule of law and private contracts still exists in 50-300 years.

There's an expression called ruling from the grave to reflect the difficulty of enforcing a contract after you are dead. The same principle applies as those frozen people are dead in every legal sense and practical sense and likely any biological sense.

I would be extremely motivated to revive them and promote reviving them because I would also want to be frozen and revived. I assume this would be even moreso the case if society develops reviving technology, and therefore knows it actually works.

Yet people, doctors and civilians, try to save people who are legally dead every day…