They'll completely change how we treat disease and prolong our lifespan
Once they're sophisticated and precise enough, these mini-machines have the potential to upend modern medicine as we know it. Forget dosing yourself with antibiotics when you get an infection, or going through chemotherapy to rid yourself of cancer. Instead, doctors could prescribe tiny bots that have been specifically engineered to target your plagued cells. Once deployed, they could deliver medicine or even perform microsurgeries -- removing diseased tissue, or mending damaged bones.
Once disease can so easily be eradicated from our bodies, and we can proactively address every potential problem area, we'll reach a point in which the human body doesn't decay at the same rate. The average human lifespan could extend well past what we've ever considered possible -- that is, unless the scientists are right and we max out at 115 no matter what.