I don't know that the problem is so much "offence" as it is reinforcing what has historically been an exclusive culture. As has been pointed out, regardless of the intent of the name, it is going to put off some people. Imagine sitting next to a friend, perhaps just getting introduced to the command line, and telling them, "Hmm... let's check what Bro says!" It just gives a certain connotation.

As a bit more extreme example, imagine a command line tool called "aryan". Sure, the name in and of itself might not be offensive, strictly speaking, but it's definitely something that would, and should, be frowned upon. The word has some important connotations.