That had two things going against it.
First was that both teams came from the same rather small geographic area which limited nation wide interest.
Second, and I think more important, was that there was not a long standing rivalry between the two teams. Mets are a fairly new team, only going back to the early '60s.
Yanks and Dodgers have a rivalry going for over a century, it would have been a west coast v. eastern seaboard as well as a CA v. NY series. Wide national appeal, even if nothing but to see the team you hate the most get stomped.
This Series will be TX v. DC. Symbolic of rugged individualism against the political machine. Or Wild West against staid and stodgy Eastern Propriety.