My parents, born in the mid-1950s are currently in the job market looking for work, and they claim they feel the ageism/discrimination but it completely baffles me as a younger person.
As a person who celebrated Y2K in public school, now in the workforce blazing my own trail: I personally wouldnt have any issue with your age whatsoever. I gauge people based on results and performance, and so if you're an old dog I dont need to teach you any new tricks, you're probably a pro already!
I would be a little intimidated by your age, and it would be humbling and awkward for me to feel like you were my subordinate, but I would cherish your insight and experience (and hopefully mature reasoning skills) and I believe you may have a lot to offer!
I still prepare resumes and cover letters for my parents as they hunt for jobs, and I wish I could encourage you as well.
Age != youth
Age != ability
Age == how many pages have been turned in the 'Book of You'
Best of luck as you put yourself out there!