Does charging someone with a crime, doing nothing about it for 20 years, and not even telling them, actually help a DA? Shouldn't the number of filed charges si

Does charging someone with a crime, doing nothing about it for 20 years, and not even telling them, actually help a DA? Shouldn't the number of filed charges sitting idle count against them, if anything? It would seem like evidence that the DA is, so to speak, all talk and no action.