It is possible to add more output methods for logical decoding. For details, see
src/backend/replication/logical/logicalfuncs.c. Essentially, three functions need to be provided: one to read WAL, one to prepare writing output, and one to write the output (see Section 48.6.5).
If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.