I get that black folk may get mistaken more for "help" in certain contexts more than perhaps some white old dude. A lot of it depends on context, age of the persons, body language, etc. But if someone makes a mistake, that does not necessarily mean it is racially motivated (let alone racist).
Body language matters
Ed Driscol: Michelle Obama's Rashomon Racism...
Instapundit: Probably NOT racism (but when it comes to skin the Obamas' have thin ones)
Ben Shapiro: The New Jim Crow