The fact that 20 NFL positions are basically 29-31, then you have RBs at 27 and QBs at 39 is wild.
32 definitely seems to be the magic number for a lot of positions. RBs definitely hit that wall hard, but safeties absolutely seem to as well.
It's alway interesting to see technique making up for loss of elite athletic ability and what positions are the best examples (WR, CB).
DT may be the position that "ages" the best, and it's surprising given the physical nature. Perhaps it's the rotation?