Is  fluorocarbon line better than monofilament ?

Fluorocarbon  IS MONOFILAMENT, monofilament is not synonymous of Nylon.

Is Fluorocarbon "better" than Nylon ? No and the opposite is also true, Nylon is better than Fluorocarbon for certain applications and FC is better than Nylon for other applications.

Personally, and I have fished with FC, there´s nothing "special" about FC that would make me change Nylon or Copoly lines for pure FC, price has never been an issue.

Where and how you fish also plays into whether FC makes sense for you.  In super clear water, and with pressured fish, it can make a difference because it minimizes visibility and it's density and fast-sinking quality can be beneficial for bottom contact baits.  That being said, that same sinking quality can totally screw up the action of many topwater baits.