Lots of people grew up in an era where we never played the Jacks. We didn't play them in a single league game from 1965 to 1980. They'd class Bristol City as bigger rivals.
We only played the Wurzels 10 times between 1974 and 2000, but we've played them more often than Swansea since then. I still think that the Jacks are currently our biggest rivals. I'm certainly in a worse mood after we lose to them.