The current SC will leave the decision to the next one. However, we see no reason to avoid the usual backwards compatibility policy: the field can be deprecated with a compiler warning, and removed after a minimum of two releases.
If there’s a pressing reason to remove it now, please put it in the PEP. An extra pointer in all dicts isn’t great, but also not terrible if it’d just be there for the deprecation period.
— Petr, on behalf of the SC