Well, yes, some of those peoples are still around, which matters to racists and fascists, who believe that races and peoples have rights and share collective guilt. None of those people are still around, which is what matters from the point of justice and liberty.
It was the peoples who owned the land. They were very much territorial. In some cases, land was owned by a smaller group like a tribe or tribelet. The land was taken from them collectively, so any redress must be to them collectively. You might not recognize the value of the collective, but they do.
The truth is that the land you currently possess was taken from the prior owners by force. It's quite possible that they or their descendants are still around, and if you actually believed that taking property by force is wrong, you'd give it back to them. You don't, but you sure to like to claim the moral high ground that you're not even vaguely close to approaching. There's no way you can in good conscience sit there and rant about property rights you clearly don't believe in, and also be taken seriously.