When you have biological reproduction, they are nearly guaranteed.
That’s because of the architecture of the cell that overcomes the natural tendency (as in Gibbs free energy) for the heterochiral/racemic state through a process of metabolism and highly specific construction of the cell. Without a cell, the chances of random behavior are unlikely to be remediated.
A robot can get 100% fair coins heads because it has energy and machinery to overcome the effects of random flips. The machinery of the cell does a lot of NET re-orientation of molecules that would otherwise be randomly oriented. One example in biology is the metabolic pathway in plants that can digest D-amino acids created by bacterial soil. But that is not a random pathway, that is a by a complex biochemical machine.