At ten feet you cannot assess a cuticle, a fibre or a knot. You can only see shape and mass, which is exactly what gives a wig away.
Real hairlines are sparse
Hair does not start abruptly at full density along a clean line.
It thins, scatters and grows irregularly for a centimetre or more.
So density at the front is the tell
A blunt dense front reads as a helmet at a distance, whatever the fibre.
Graduated density with a plucked front reads as hair before anything else does.
Knots are the close-up version
Each tied strand starts at a knot, which reads as a tiny dark dot on lace.
Bleaching the knots removes the dot where the lace allows it.
What to specify
A density percentage, graduated at the front, plucked hairline, knots treated.
Then judge the sample from across the room, not in your hand.