Retired certificants aren't usually considered in policy-making...at least until a huge portion of the pool is about to retire. Organizations logically fear the financial implications of losing a large portion of certificants. That's understandable, but not a good enough reason to jump on the certification retired classification bandwagon. There are many issues here that need to be considered.
First and foremost, organizations should have a policy covering use of the designation and associated acronym, and if an individual lets a certification lapse, he or she should no longer use the credential. That includes retirees. If the certification lapses, you no longer have it. Period. Organizations should have procedures for how to communicate this to individuals whose certifications lapse and to those who continue to use the credential despite being told otherwise.
Holding your certification / credential should mean something ...and if you have some individuals who are meeting ongoing competency requirements and others aren't, but they all hold the same credential, then the meaning is mixed. Some try to address this by having active and retired categories of certification, which is good in theory, but falls apart if they let all certificants use the same exact credential and no one other than the retiree and the certifying organization knows which category of certificant they are.
If your certification focus is on public protection, then you want to do your best to ensure your certificants are competent. Telling some certificants they don't need to do anything to improve or demonstrate competency anymore while still holding up the same designation as others isn't consistent with the public protection focus. If all use the same designation and/or associated acronym there is no way for consumers to know which are required. So, if you have decided you want a retired category, at minimum, clearly distinguish it with a different designation/acronyn - because it is a different credential.
Also, many of the retired classes of certification I've seen are based on age alone. But we all know that not everyone retires at 65. How do you know if they are practicing or not? One way to handle this if you have a retired class is requiring a signature attestation that the individuals are, in fact, retired from the role that you are certifying.