Reports

The problem in my case was clearly shown in the logs. I had an unused replication slot that was causing issues. My solution was to drop that slot and explicitly define the schema of my tables in the trigger function, like this:

CREATE OR REPLACE FUNCTION distribute_data()
RETURNS TRIGGER 
AS $FUNCTION$
BEGIN
    INSERT INTO public.pub_insert_a(a) VALUES (NEW.a);
    INSERT INTO public.pub_insert_b(b) VALUES (NEW.b);
    RETURN NEW;
END;
$FUNCTION$ LANGUAGE plpgsql;

CREATE OR REPLACE TRIGGER distribute_data_trigger
AFTER INSERT ON pub_test
FOR EACH ROW 
EXECUTE FUNCTION distribute_data();

And I enabled my trigger as REPLICA
ALTER TABLE pub_test ENABLE REPLICA TRIGGER distribute_data_trigger;

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