"The System" does sound like conspiracy nonsense, yes. That implies there's some invisible power structure scheming behind the scenes for world domination.
If there's no system, there's no systematic racism.

But yes, you're right. In the context I use the word, I do believe there's an "invisible power structure". They're not scheming for world domination, they are maintaining it. Nothing changes when different ideologies win power, so why would you believe power has actually changed hands? Why didn't Obama fix these racist laws? Either because he didn't want to, or he couldn't.

There's a lot to unpack here. So athletes, private businesses and celebrities are also "system"?
Elite athletes that have huge social influence and are used as pawns, yes. Major corporations, yes. Megacelebs who appear to lack any actual talent, yes. I mean, some people and businesses think BLM is a force for good. Others think it's good for business to be on their side. But BLM has large scale "system" support, that is obvious. So my point remains... if the system tolerates and even supports their existence, then they are not a threat to the system.

What do you think BLM are fighting against? Where is this racism if the "system" doesn't exist?