"Can people incorrectly lionize the past of their own cultures, a past they never even experienced and don't even have the excuse of nostalgia for?"

[quick glance at any number of reactionaries, revanchists, and nationalists]

Yes. Next question.

It's not credited, there's just a picture of an indigenous person that people aren't expected to recognize. The image is meant to imply that this is how all indigenous people lived by not specifying, using the words of one singular person from one singular nation to do so, which may not even be true to such an extent. The image is taking the quote and using it to perpetuate the myth.

Yes.