Hugging and kissing is a sign of affection, which is what exists between friends.
Now, with Covid, we need to be more careful, but rejecting a hug from a close friend or family member, without explanation can be very hurtful.
If both participants have been vaccinated and boosted, the risks are reduced, and the hug can be beneficial to their mental health.
I remember one lady saying to the minister as she shook hands to leave after the service, "That's the first human contact I've had in the last week"
Note how animals, particularly cats make contact when they meet. We need physical contact, albeit now, as safely as possible.