Some of this was covered in
this thread and also
here.
If effective cloning and forced growth are available in the 3I by a certain point (T5 p121 & p505) then cybernetics become unnecessary for normal people. Given the nasty things that could be done with cybernetic parts, it doesn't seem unreasonable for society to see those who prefer to be cyborgs as aberrant and either shun them or keep a close eye on them. There'd be a tech window where cloning new body parts for medical replacement wasn't widespread, but even at TL12 (the high point on the bell curve for technology in the 3I?) Early (T5 p500) replacement could be available and carried out in hospitals.
It doesn't seem logical in 3I society to turn an individual into chattel because they've lost their legs and an arm in a shark attack while on holiday, then had them replaced with prosthetics. But a person who choses cyberlimbs or weapons and bug eyes a-la Neuromancer could be assessed as a crime or public safety risk by security authorities.
On the original topic: maybe it's not noticed because they become further and further seamlessly embedded in society the higher the TL goes? People don't notice them as much because they're used to them and the things are designed to be unobtrusive?