Acccording to Lady C was Princess Anne the Princess Royal who is behind the claims of racism, but in reality isn't at all racist with what she asked, essentially as a brief thing is that she was asking if Archie would appreciate being born of the royal family or not as her blatant ignorance of different cultures and then the rest of it.
I know for a fact that with (not sure if someones already stated this) not getting a title has nothing to do with skin colour whatsoever its actually due to George V setting forth that no one beyond grandchildren were to get one, even still before being married is always a style like when W&H were at the RMA Sandhurst doing army officer training were styled W&H of Wales since there cant be two title holders.
With styles Lady C married the heir to the title that is in the possession as such of the Chief of Clan Campbell, their title is the Duke of Argyll (Duke stemming from the Latin word dux or whichever you want to call it meaning leader, is the highest ranking of the aristocracy) in Scotland, the heir being styled Lord Campbell, as is Clan Bruce the title being Earl Elgin and the heir being Lord Bruce
Though now no one gets a hereditary title anymore other than members of the royal family as there's no point in it since they were prevented from sitting and voting in the House of Lords (after sometime in the 70s being reduced to about I think 20% of them as barely any of them bothered turning up), which has led onto a lot of the seats (like Inverary Castle being the seat of the Campbells in Argyll has sort of become a museum others have become hotels for other hereditary peerages. Althorp being the seat of the Spencers
There's therefore some at least peers in the House of Lords without a title as well, also Princess Anne's children Peter Philips and Zara Tindall dont have either