I'm 33, also 5'8''/133 lbs, didn't run in HS, didn't run in college, started jogging occasionally in early 20s to lose weight (was 200 lbs at the time) and took up distance running seriously in my late 20s. I don't have any special talent as I'm more of an endurance type (400/800 pb's are 62/2:16).
I'm consistently following my own customized Daniels/Tinman training plan for the last 5 years with relatively modest mileage of about 50 mpw (with only few weeks per year going into 70-80 mpw range). I do not do periodisation/base training, instead I believe that the key is to do repetitions and threshold training year round and buffer harder/anaerobic training and racing with adequate amounts of very easy/recovery jogging. I'm also into orienteering sport so around 20-30% mileage is offroad/hilly/forest running that requires lots of core strength. My PBs as of now are 9:28 for 3k, 16:3x for 5k, 34:5x for 10k and 1:15:4x for HM. Half-marathon pb was set just two months ago on difficult hilly course with over 700+ feet total climb. I still believe I can break 16:00/34:00 at some point in upcoming years.
So I think you can go well below 17:00/35:00 with consistent training that involves big variations of quality functional training. The single most important advice from me is to train smart, be consistent, don't overdo it and do your easy runs easy. The biggest problem what I see is that many runners either run their easy runs too fast and doesn't work on their threshold enough.