I'll just note that the Giants lost the 1989 World Series in 4 to the worst era of the A's. Sorry, Giants, that's not a good sign.
Taylor Swift is a small price to pay for a third World Series Championship, should it come to that. Go Giants!
The worst era of the A's? Three AL pennants in as many years doesn't strike me as "the worst" era of any baseball team, for any value of "the worst" that makes sense.
The LaRussa, McGwire and Canseco era. So yeah, the worst.