I feel like you do have a point. The only case that I've heard δείχνω without σε κάποιον (somebody) in Greek, is in case of emotion, where δείχνω actually means seems, synonymous of φαίνεται. Or in case of directions.
(Αυτός) δείχνει/φαίνεται ήρεμος - He seems calm.
Φαίνεσαι/Δείχνεις ανήσυχος, είσαι καλά; - You seem worried, are you okay?
Αυτή δείχνει προς το μέρος τους - She is pointing towards them.
We might need to look into this one. Thank you. ^.^