By that logic, everyone other than certain rich WASPs were historically disfavored.
I mean...yes?
Again, seems too broad a definition to me. While both Black Americans and Irish Americans were historically disfavored, it seems dishonest to classify those historical experiences under the same umbrella.
Putting two things under the same umbrella doesn’t mean that you are saying that they were equal. It is an objective fact that Black Americans and Irish Americans, both faced discrimination. nobody is saying that a history of slavery in Jim Crow segregation is comparable to a brief period of employment discrimination, but it’s an undeniable fact that both groups faced oppression by dominant group in America. Again, this is just the definition of the word.
A pickpocket and an armed bank robber are both thieves. Chickenpox and cancer are both diseases. Categorization does not imply equivalency.