"But rights depend upon 'personal sentiment or arbitrary morals' all the time. Who I rent out my upstairs room to - I'll decide. Which clubs I join; what movie theatres I frequent. And these things have economic/social impact beyond me - the theatre will close if it doesn't show movies acceptable to a large enough population etc."
Economics doesn't factor into law. SCOTUS on the matter of Equal Protection has already spoken so economies adjust to legal realities (not vice versa).
"So we argue about 'privilege' like that can make a difference. Its at root, the majority vs minorities. The game will always be slanted toward the majority, because free market etc."
Privilege in racism is the concept that you and I based on our ethnicity can take certain conditions for granted. For example, I'm white so I rarely feel need to change my behavior when a police patrol car passes me on the road but a person of color is acutely aware of the situation and must act above/beyond what the well adjusted citizen should act (more polite, more timid). Privilege is the freedom to not notice a power disparity since you have all the power or the social norms in your favor to acquire it. Markets don't factor into it either. Markets are the affect of social orders not their cause.
"We have folks making up rules on every side; inventing new words and theories and constructs. And shouting down folks from other viewpoints. Its all designed to impede real dialog."
Okay, I'm not going too mean here but do you realize that POC aren't a position of power, right? If I get caught with a blunt I'm more likely to get a slap on the wrist since I'm white versus a person of color who may get a judge who'll throw the book at them. Just by being white I have a statistically better chance of lesser sentence for just about any crime.
Just because POC say mean things to you on Twitter or to your face doesn't equate being shouted down. They (and you) have a right to not associate nor to consider any ideas if they (and you) so wish. So, please don't assume the "truth is the middle." It's time for people to just accept that the truth in this matter be it racial equality or LGBT (emphasis on the T imo) rights is very clear. The only debate should be on how best to handle the injustices in question.