Quoting Marc-Andre Lemburg:
"""
The support for the wctype functions should have been remove long ago,
since they cause subtle incompatibilities between Python builds. I should
have probably never added it in the first place... people were worried
about the size of the type record tables at the time, which is why
I thought it would be a good idea to try to optionally use the C lib
functions.

The comment was true before the Python type tables were changed
into a type record database: the switch used to remove the
Python tables required for those functions. With the type records
database, this is no longer the case, since the records are also
being used for properties that are not exposed via wctype functions.
"""