It wouldn't surprise me that it would be because of a software block by Apple because that's the kind of thing that they like to do (but this is complete speculation).
Because a lot of the security stuff is aimed at making it harder even for people with relatively unlimited resources, like nation states, to break into someone's machine.
Like if one has a TouchID sensor paired with a certain Secure Enclave at the factory or with Apple authorized tools one can be fairly certain that an intelligence agency can't (easily at least) just take swap the factory TouchID sensor for a compromised one. It may not be 100% fool proof but it also has the effect of forcing adversaries to focus on specific targets instead of being able to use a dragnet style approach.
