It's been the case for all North American politics, for a long time. I'm giving him the benefit of the doubt, as is, but he broke some promises already. The first one had to do with adopting the UN policy that's called "United Nations Declaration on the Rights of Indigenous Peoples." Then there's the failed promise to give Natives the right to veto any natural resource development, and lifting the cap on funding for First Nations funding.
What'll really drive them away are his environmental decisions currently, despite it not breaking an actual promise. Not one, but two pipelines. Enbridge and Kinder Morgan's. In denying a third, he just barely managed to scrape by since he avoided Northwest BC and the Great Bear Rainforest. Lots of outrage there, still, and largely from those groups.
He's done some good, at the very least. Allocated funding (69 million over 3 years) toward mental health services for Indigenous peoples. Still a while left, though, and with a majority government maybe he'll manage to make good on his plans in this department. Some he's working toward right now are: ensuring clean water availability (a lot of them were screwed by oil in Alberta), funding the Freedom Road project (which grants residents of Shoal Lake access to, y'know, the world, as they're currently isolated), and meeting with various Native Leaders once per year.
If you're ever curious about how he's doing with keeping his promises, there's actually a site that keeps track of all his campaign plans/promises which marks it as failed/in progress/complete, and cites them with relevant news articles. You can also specify which category you'd like to see (economical, culture, environment, gov, immigration, indigenous peoples, security).
Current standing:
67/233 in progress
38/233 achieved
28/233 broken
Oh, absolutely. And with our southern neighbours' current standing, there's going to be a real uphill climb for him in combatting the rhetoric we're being fed come the next election.
Seems he's doing
okay with them, but his environmental decisions are going to be a deal breaker in getting the Aboriginal vote again unless he makes good on what's remaining.