IANA delegates each ccTLD to a manager in or for the territory concerned, and that manager sets policy under local law. This is the key difference from gTLDs, which operate under contracts with ICANN: a ccTLD decides for itself who may register, whether residency or documents are required, how disputes are resolved, what a lookup shows, and whether to offer RDAP at all.
Some ccTLDs are open to everyone and are marketed as if they were generic because of what their letters suggest: .io, .ai, .tv, .co and .me are the usual examples. They remain country codes, and their future is tied to the ISO code and the policies of the territory.
There are also internationalised ccTLDs written in local scripts, such as .рф for Russia. Search engines generally treat a ccTLD as a signal that a site targets that country, with exceptions for the generically used ones.