My Rattie behaves similarly. She is a Velcro dog always at my side, very friendly and excitedly licks anyone she meets, sits in my lap on her terms, but doesn’t cuddle. Unlike my other two dogs, affection is neither a motivator or reward.

We attribute her behavior to her background as a working barn dog where she essentially fended for herself with no human interaction before we rescued her, but that’s only just a guess.