I had a non-contrast mri by end 2017 and the result was mild bilateral temporal lobe atrophy for patient's stated age, otherwise everything is normal. it was very mild, not disease specific. i got freaked and did not follow-up. should i worry?

More information is needed. This is not answered by reading the results of the MRI alone, but asking for example why was a brain mRI ordered. See your doctor who can see the entire picture.

Your best answers to the significance if this result would be to conference with the radiologist and your doctor. Generically, the result may be a minor congenital anomaly, but could be an issue which runs in your family. Some dementias, especially front-temporal variants may show such patterns, but unlikely to be a problem if symptoms are absent in you. Don't worry, have your doctors explain.