Age does not cause optic nerve atrophy.
The optic nerve does not shrink with age, but optic nerve atrophy is usually due to pathologic factors, such as glaucoma, optic neuritis, ischemic optic neuropathy, diabetic retinopathy, etc. Patients with nerve atrophy will experience vision loss, narrowing of the field of vision, etc., and should consult a doctor to find out the specific cause.
Ageing does cause eye-related aging phenomena, such as presbyopia, cataracts and so on.
If you experience eye discomfort, you should consult your doctor to find out the cause and take targeted treatment.