How do you know that he doesn’t mean it in the medical sense? Would fit, too

The error rate is probably pretty high. There are people with a “baby face” as well as people who look older than they are. Even the best AI can’t predict something that isn’t predictable, like the age by looking at a photo. You can get rough estimates, but no AI can discern between a 17,9 year old and a 18 year old.