You alluded to the analogy of a tree and bearing fruit. We might agree that the human ‘tree’ has become rotten and its fruit is bad.
We don’t believe that in being ‘born again’ the tree is knocked down and a new one planted. Rather, we would see it as a new birth or new growth for the tree. With fertilization and pesticide it is regenerated and that which rots it is destroyed. Sort of like a plant which you thought was dead, but with proper nurturing, comes back to life and is healthier than ever.