Much better? Come, now. I do think his best level is better - he's got more magic, more awe-inspiring moments. But much? Seems like Irish hyperbolic poetry to me. I mean, look at Roland Garros. Carlos is a more established clay player, but he still just barely beat Jannik.
Anyhow, I'm of two minds about the importance of the final. On one hand, it is big for both: For Carlos, it will be a huge boost in confidence that he can beat Jannik on hards and stop the momentum swing. For Jannik, it is less about winning it and more about not losing. Winning would be nice for momentum, but losing might plant a seed of doubt.
On the other, both of these guys are true champions, not just in terms of their physical talent but their mentality. When Cincy is over, the winner will celebrate, the loser reflect, but both will quickly move on to prepare for the US Open and bring their best there.
Think for a moment about what Jannik did just a month ago: After losing a heart-breaking squeaker in which he was the clear underdog at Roland Garros, he turned around and beat Carlos at arguably his best Slam. Or think of how Carlos will go AWOL in a given match, or even period of a season, then focus in and blow everyone away. The point being, regardless of tomorrow's outcome, both will be focused and ready for the US Open.