Right now everyone is under attack by a very sophisticated propaganda attack. I am not sure which lady you are talking about. But I can say that right now when people say something like BLM, they are immediately slammed with 'All Lives Matter' or something of the sort constantly as a way to degrade what BLM stands for.
While other people at the same times are 'programmed' to say things like 'All lives matter' by getting shown propaganda that makes them feel like it is also an important thing to say.
That is why the first step is to diagnose what you are being shown. Be it on TV, Radio, certain websites/platforms, etc. BLM is in no way saying that other people are not important, but if you can program people into thinking that it does, you get some instant and unnecessary arguments.