Maybe there isn't a less verbose way. It just seems like a bit much that I have to take the jsonb array, convert it into a relation so that SELECT can operate on it, only so that I can sort it, and then convert it back into a jsonb array object. I was hoping for something like json_table2.aggSort("portal_name"). I'm not actually using json_table2 as a name, that was just for my minimalist example. As mentioned, my real project consists of refactoring a pgsql function which uses TEMP tables to NOT use temp tables, but instead, JSONB objects.
PostgreSQL is closer to "pure functional" than "object oriented" if that helps explain things. We do a thorough job of documenting the functions we do have and a quick skim of the json related functions does not reveal any with a signature like: jsonb_sort(array_of_objects_json_array_value jsonb, top_level_object_key_name__or_path text). You might want to post that as a feature request on -general and see what others more familiar with the json implementation think about the idea - we have jsonb_set and jsonb_insert so the request isn't completely novel - but as it stands today the whole "dis-assemble->act->re-assemble" flow is the one that we are stuck with.