I'm not sure "politically correct" is a precise term.
Some of the indigenous people are undoubtedly offended by the term, but most, apparently, do not take offense. Does the fact that some take offense carry enough weight to have the term banned from polite society?
Ideally, one could refer to the specific indigenous "nation," if known.
How often does it come up? I can't remember the last time the subject of indigenous people came up in one of my casual conversations. The last several times it was even remotely relevant it was in reference to a sports team. Who gives a serious ****?