I'm not sure if there are any examples of this happening (if at all), but given how many domain extensions that are available today, can any domain extension that do not offer domain privacy offer it in the future?
In most cases, for a given TLD you have its (sole) registry and then many registrars (there are exceptions of course). Then you have separately "proxy services". When you, through a registrar, register a domain name at the registry, if you carefully read the registry-registrant contract you will see that you are forced to give true information and any error may lead to the domain being taken back from you or deleted.
Now, 2 things happen :
- because of various EU rules, EU based registries are mandated to take extra care of personal information (for physical persons); in many cases they make sure it is not publicly seen, for example in
whoisoutput. This is the case for example for
.FR. The registry still has your full data, but just protect it
- various registrars and third parties proxy services provide you with a service where they put their own data as owner of the domain name but make sure all contacts, for example through email, are redirected to you, since you have a contract with them. It is only in this way that your information is undisclosed to the registry but it has drawbacks also: in case of problems, you are not, for the registry, the true owner of the domain. So for really high value domain names people/companies choose to do the same thing but use their attorney or something like that as proxy.
On top of that, for gTLDs, you have an ICANN program that registrars are mandated to follow where they at least annually contact their client and make sure the information is correct, and ask them to correct it if not. Failure to do that may lead to the domain name being deleted.
As for ccTLDs, the legal rules they have to follow may change and they may need to adapt. So privacy handling may change in the future. But I think you will have more chance having providers (registrars or third parties) starting or stopping to provide services like that than having registry change their rules.
For gTLDs registries (under contract with ICANN) it would be very hard for them to provide services like that, they would need a lot of arguing, and it is only when local laws are contradictory that they would more easily be able to do that (see
.CAT cases in the past).