This is a spin-off from w3c/html-aria#64. To save people the trouble of clicking, what I stated there is:

@stevefaulkner: I'd like to triple check something to be sure we don't have unwanted side effects.

The ARIA 1.1 region role was modified and has several noteworthy characteristics that were not present in 1.0, namely:

• region subclasses the landmark role
• "Authors SHOULD limit use of the region role to sections containing content with a purpose that is not accurately described by one of the other landmark roles, such as main, complementary, or navigation."
• "Authors MUST give each element with role region a brief label that describes the purpose of the content in the region."

As a result, the Core AAM maps the region role unconditionally to the platform role associated with landmarks.

With the above in mind, your statement that

section always maps to region, it is only announced by AT when it has an accessible name.

Implies that every screen reader on every platform is going to have to sanity check landmarks just in case it's a section element that isn't named -- unless somebody changes something somewhere. Given what you've said in this issue, it seems to me that we should open an additional issue against the Core AAM with conditional platform mappings based on the presence or absence of a name. Do you concur, @stevefaulkner?

Steve hasn't replied yet. But I'm going to error on the side of caution and assume his answer will be agreement rather than calling me a fool. ;) If I'm wrong about that, we can close this issue. Otherwise, we need to make this change in the Core AAM because having to sanity check a valid, non-generic role "just in case" sucks. Doubly so when every screen reader might be stuck doing so.