In all fairness, all of society, not just the WT, held prejudiced and bigoted ideals and not only was is acceptable, it was encouraged.
There were lots of "scientific" (i.e. pseudo) skulduggery adventures where "scientists" presented evidence of caucasian superiority over the "dark" races with things like cranial capacity, facial features, intelligence, etc.
My now deceased, long time JW grandmother would say racist things (especially when she developed dementia) without a trace of malice (e.g. she would say 'colored,' and 'picaninny'). "It was just how it was in those days" was the explanation. Hell, one of her best little old lady friends was an equally elderly black woman. That doesn't excuse it, but it was interesting how my grandmother could think those things and then have a black woman as a good friend, and not have any cognitive dissonance about it.
I guess back then people thought that it was rational, and even supported by science, to believe that whites were superior.