I'm Canadian and every time I hear the misconception that we're a magical land of super nice people where racism and bad stuff doesn't exist, I find myself wanting to laugh and cry and scream all at the same time.
As for the question whites ask, "why should I feel guilty about stuff that happened so long ago?" You're right, it wasn't that long ago. But even more than that, the legacy of generational trauma is real. First Nations peoples, Blacks, etc are still living with the effects of the past. Further, nobody is asking anyone to feel guilty, we're asking for the truth to be acknowledged, to be recognized. There's an old saying...those who don't know history are doomed to repeat it