So far as I can tell, the setting is not nailed down except "the Old West." Well, that was an era where there was a lot of resistance to white domination from the Native American nations that had been forced out west. The Battle of Little Bighorn, the Ghost Dances, the Wounded Knee Masscre all come to mind as examples of Native Americans trying to preserve their cultures in the face of white domination. So to me, there's something deeply troubling about seeing a member of an oppressed community, Tonto, willingly subordinating himself to a white man-- especially one like the Ranger, whose goal is to aid in "civilizing the frontier," which in reality meant solidifying whites' hold over the West and the Native American nations who lived there.
Well, one mustn't generalize about white people any more than any other race. There must've been some white people on the frontier who had no such imperialist agenda and just wanted to keep the peace. The Lone Ranger could easily be one of those. Whatever the political underpinnings of the original, a remake doesn't have to be enslaved to them.
I've recently been revisiting Filmation's
The New Adventures of the Lone Ranger animated series from 1980. Filmation was usually pretty progressive in its depiction of racial diversity, and in its casting. In this version, Tonto (played by Native American actor Ivan Naranjo) was an equal, not a subordinate, to the Lone Ranger, and was an official deputy of his tribe, even taking the lead in an episode dealing with the enforcement of tribal law (where the bad guy was a cavalry commander who had just the kind of imperialist attitudes you're decrying, and our heroes had to teach him the error of his ways).
Although you're right about the setting not being nailed down. Since this was in the days when animated shows were obligated to be at least nominally educational, there were a lot of episodes in the Filmation series built around real personages and events from the Old West -- yet they ranged at least from 1861 to 1889, not in chronological order, and the Ranger, Tonto, and their horses stayed the same ages throughout.