Not easy you could say artificial above 30 but it is hard you mostly here have only geometry to make your assumptions from the rendering is not as clear as you also would wish to rate age with higher precision based on the skin state + geometry (skull).
We are analyzing a lot if someone stands in front of us it is much easier to detect everything
A really good Photographer can make old look much much younger and he doesn't need Photoshop for it only skill capturing the right moment under the right conditions.
Over exposing is a common cheat in beauty shooting to eliminate high skin frequencies of course makeup is the easiest way to fool a camera and not trained persons.
Then we have the entire Digital Path where Manipulation opportunities are pretty endless.
And we all ready enter the AGE of Realtime Manipulations of Real Humans Life input.
Realtime Human Daz is growing.
It still looks rather childish and mostly is used on Smartphones for Entertainment mostly but it's going to evolve rapidly into a quality state where we absolutely will not be able to tell by our visual recognition if a person is real or not on a digital output.