I think it's very individual whether you have to start late in life to run well as a senior.
I'm 67 and a lifelong runner. Never had the initial basic talent to set overall age group records, but do have state records I set in my 50s, and I ran the all-time second fastest time in my event in the World Senior Games another decade on from that.
Had knee surgery at 46, and again at 57, and got back to good form since. Have been fighting an injury problem for the last 18 months (I think coming back from various injuries lead to right glute/hip flexor/quad weakness), and in spring was down to a mile of walk 100m/jog 100m. Been working with a physio and a lot of strengthening exercises, and now running three times a week (2x20 min on treadmill and 1x3 miles on track). A lot of Elliptical training when I couldn't run. It's really been an 18 month project to begin to reverse the decline
Two years ago, I ran 19:45 from 5k, today I'd be about 27 min, but gradually improving, and goal is to make it back to around the 20 min range.
I was never quite as good as you (I was more like 17:30 5k in my mid-50s), but being able to train and compete is extremely important to me (although I'm still very much engaged with my career).
Obviously I don't know what your physical issues are, but it seems to me the options are (assuming there is just absolutely no fix) to commit to fix the issues and work through the process, accepting that you probably won't get back 17:00 (although to put that in proportion you were - like all of us - going to get slower). Personally, I found that there was plenty of satisfaction in training to run under 20 min at 65, but there may be a mark where I find it's so slow that it's not something I want to do.
Without knowing your issues, I would guess there is a good chance at a comeback, if you want to put in the time and effort, and while you likely won't see 17:00 again, only you can decide if running (say) sub-18:00 at 60 is worth it or not. You were obviously a nationally competitive level age group runner, and likely can be again even if it's older and slower.
If currently, time and life in general doesn't lend to that commitment, then it's question of coming to accept that for a period you aren't going to be a competitive runner. If so, I'd suggest you still make keeping physical fit a priority (maybe elliptical, stationary bike, weights) and down the road the issues may take care of themselves, and you might feel like a comeback.
Whichever way you go, good luck.