Not every tissue in the body likes to be pulled on. Nerves, fascia, ligaments, joints- they don’t get better with being pulled.
The spine and skull are meant to house the brain and spinal cord. These structures can move in awkward, non- functional directions, but it doesn’t mean they appreciate it, or won’t be painful.
Stretching and bending the head and neck to the side to stretch, or to build up strength goes directly against the spine’s biomechanics.