It's true that many first nations people struggle. Canada is taking steps to help them (see accelerated vaccination of native communities) and I sincerely wish them all the best. However, dismantling the police probably isn't going to undo things that happened several centuries ago.
In fact, I am no sociologist, but I would surmise that telling cops that all of them are bastards and exposing them to budget cuts will probably make them behave with less kindness, not more. ACAB is the opposite of constructive. In my opinion, it's a toxic message with the potential to make things worse for everyone, first nations included.
All of that being said, I'm 100% in favor of body cameras that are always enabled, and stricter limits on weapons use by police.
Consider that your viewport is small enough that the rougher parts of Canadian life for minorities are invisible to you.
Canada has some major problems with racism, and a lot of news media (particularly in the PostMedia family) is fanning those flames.
The First Nations have more recent and direct issues with the police than the founding of Canada: https://en.wikipedia.org/wiki/Saskatoon_freezing_deaths