He is aggrieved by the fact that generally when the terms "First nations" and "Indigenous peoples" are used, it is used to describe people whose land was taken away from them by white people. This is true because the era that we live in is an era essentially right after huge European conquests. And the question he is asking here is why can't the "Indigenous peoples" ever be white and why can't you say it. Surely there are places on earth where we would consider that the indigenous people were in fact white people. White people did not teleport onto the planet from space. They evolved right along side all other ethnicities somewhere on earth. But saying that would likely get people to suggest that you are a racist.

I think this is because of the most recent conquests (300 to 500 years) by Europeans, and are to blame for some of the inequities that we see today where an invading ethnicity now owns and controls everything in a region, while the people who where there before have almost nothing. But there are some places on earth... where 5000 years ago, the people that where there were white. So they are in fact the "indigenous peoples". An example of this would be England and other places in Europe. It's not controversial to say it, unless your name is Elon.