Jameson ... harks back to the time when newspapers were run by individuals, and sometimes arbitrarily.

It still happens. See, for example, Teresa Heinz Kerry and the Tribune-Review (owned by Richard Mellon Scaife), which has pursued and attacked her for years. (This is not a comment on the veracity of the paper's accusations, but jast a note that it's maintained the same sort of apparently personal vendetta that JJJ does against Spider-Man.)