I would disagree. Just because the players weren’t black doesn’t make it untrue. I hate how “R&B” is really code for “black”.
It always has been .URBAN is the new code word for black music.
R&B was the name Jerry Wexler (Atlantic Records) came up with in attempt to change the chart designation from "race records" to something else.
White people were likewise slurred by the establishment media. Country Western used to be called "hillbilly" in the trade publications (like Variety and Billboard). That was the chart, "the hillbilly chart". ASCAP wouldn't publish country or R&B. BMI would. When the two dejected forms morphed into rock and roll, ASCAP no longer had the hits (they wouldn't publish R&R either) so they alleged "tricks" and "payola" as the reason they no longer owned the charts.
However, Elvis and other artists DID manage to get the #1 hit on the R&B, Country, and Pop charts all at the same time. Something that the industry doesn't want to see happen ever again. The industry doesn't like small labels (whether they are called Sun or Sub-Pop) coming up with the "next big thing". Too many outdated artists are under longterm contracts to let some new fad ruin their plans and release schedules.