Wouldn't Oracle's use of the Java trademark be problematic in a trademark cancellation request? We're talking about two very similar names for identical product types (i.e. programming languages). Indeed the similarity was originally intended to imply an association. I wouldn't be surprised if Oracle's sole interest in the trademark is due to its similarity and history.

Oracle's sole interest is extracting money from its assets through whatever tactics are most effective, regardless of technical merit (not specific to JavaScript I guess though)