Many US cities have high rates of homeownership by non-white families who bought during/after White Flight. This means that there are a lot of minority homeowners who have significant real estate equity (often inherited) but lack other assets. Now the trend is reversing and white people are moving back into city centers, often renting/buying in working-class neighborhoods that had mainly been populated by minority groups since the ‘60s (aka gentrification). Sellers want to convert real estate into cash, and buyers want relatively cheap urban real estate and have cash. So the highest turnover is going to be in majority-minority areas.

(Another factor is rezoning/redevelopment, which is also putting pressure on people in some more heavily minority neighborhoods to sell.)

All of this also explains why property tax reform is such a thorny issue in cities like New York.