This is food for thought. I'm a white Canadian woman, just like the lady from your story. I'm passionate about supporting the protests in the United States, and I've been perpetuating anti-racism and anti-discrimination for as long as I can remember.
However, I always try to stay in my lane and talk very little, when it comes to the lives of African-American community. I DON'T know how it is for them, I DON'T know what they are going through. And I definitely don't want to offend anyone by pretending I'm aware of how difficult it's for them - facing rasicm. I faced discrimination many times in my life, but not racism. I'm an ally and I'm vocal about human rights, but I ALWAYS want to know if I'm overstepping.