As for "schema identifiers" vs. "schema names" - they both seem equally wrong. The list can very much contain sequences of characters that when interpreted as an identifier and looked for in the pg_namespace catalog do not find a matching entry and are therefore by definition not the name of any known schema in that database.
Besides, I hazard to guess how many times we write "table name" and "column name" in the documentation when your argument is that "table identifier" and "column identifier" is the correct choice. No, rather "name" and "identifier" in the context of database objects are known to mean the same thing - the alphabetic name of the object.
