Unfortunately, in much of the world, black lives do matter more .....in the sense that, unlike the white majority, they suffer prejudice and discrimination in many areas.
The BLM movement is not asking for privileges....merely equality.
In my opinion, the riposte ‘all lives matter’ is often intended as a denial that the black community have any cause for complaint ...as if they are making unreasonable demands. I’m sure Carrie doesn’t think so.
If your house was on fire and the fire brigade arrived, you wouldn’t expect them to start dousing all the houses in your street on the grounds that ‘everyone’s house matters’.