Everyone here is fully aware that consent cannot be given under duress, so saying the Natives agreed to it, when the alternative was being massacred by settlers and losing the land anyways, is just a sloppy form of historical revisionism.
There is no excusing or justifying his decision to sign that bill into law. You can say "times were different," but that is also true of the modern age and is the type of argument that can be repurposed for any conceivable position.
In any case, you have made numerous claims that are factually untrue and very illogical, i.e. history being destroyed and "treason" being a major concern for a nation that idolizes traitors. Note that this tactic is identical to SJWism, where emotion is allowed to overrule logic, yet logic is still considered important enough to require a thin veneer of bullshit masquerading as a rationale. But there really isn't. "Muh statue" is merely an appeal to tradition, which is again just a fallacy.