No, that isn’t true. All parts of the OAuth dance are just means to end up with a Bearer token in the Authorization header, and I don’t see why the process of obtaining this token couldn’t involve a web browser?
Plus—HTTP auth isn’t limited to Basic, Digest, and Bearer schemes. There’s nothing stopping an implementation from adding a new scheme if necessary, and add it to the IANA registry.
It's quite clear that we're using the same words with different definitions. I don't have an 'official' reference/definition for them. Unless you do we'll have to call it a day here and accept the fact that other people use the same names for different things.
Fair enough. I do think however that we both care about standards, protocols, and quality engineering, albeit with different opinions. That's got to be worth something.