Citi hasn't offered the Dividend for new customers in a long time. It definitely costs them money and they want to move people to something else. The TYPreferred is rather crap though, convert to a Double Cash if anything.
TY points are worth one cent if you redeem for mortgage or student loan payment, potentially more than one cent if you have a Premier or Prestige (with accompanying annual fee). But if you have one of those cards you have no need for the Preferred and its slow earning rate.
Anyway, stick with your Dividend.