It's my legit opinion & I only just came to this conclusion within the last year or so.
I used to sorta feel the same way you do about about token white characters in black TV shows & films. But I thought about and when it comes down to it, black TV shows & films are being produced and/or distrubuted by white Hollywood studios just like the white tv shows/films are. And whites & non-blacks reguarly watch black TV shows & films, so of course Hollywood studios/networks are gonna want token white chracters in these black tv shows/films that they produced/distribute.
And they can justify it by the fact that they put token black chracters all the time in white tv shows/films, especially nowadays with so many tv shows with a black lead/co-lead or Black chracters as part of the regular cast because of Hollywood's diversity push the last several years.
last year or so?....sure the white gf had nothing to do with the change of heart?
When a new character is added to a show, the hope is that it's seamless or that the character adds something to the show.
When these aren't the cases, audience is going to react negatively.
Take these examples of Black characters added to Black shows
Thelma's husband on Good Times & Cole's girlfriend on Martin
When a white character is just randomly thrown on a Black show, chances of it not working are increased.
And it becomes obvious that the actor is just there to attract white viewers.