Fake nails seem to be much more common in the US than they are over here. And just like any type of make-up, once it starts to become the norm, many women feel like they have to join that trend or look frumpy / unfashionable / unkempt. I'm glad fake nails aren't a big thing over here yet, although they're on the rise. I've only worn nailpolish once in my life as a teenager and I hated it (and never have had fake nails). Luckily I have pretty strong, healthy looking nails naturally so I don't look like a slob - they look like an understated elegant French manicure.
Going grey and not wearing make-up are two other things that used to be really normal and are now frowned upon. Very few ladies of my grandmother's generation ever wore anything but a little bit of lipstick when they went to town and they all went grey. I only know one woman who's going grey naturally without ever dyeing her hair. People call her a slob constantly though, not sure if they do it to her face but certainly behind her back. She's in a field where looks shouldn't matter (as a medical doctor and a PhD) and she's very meticulous in her job but her grey hair puts people off.
Funny: in engineering, grey hair gets you promoted because it suggests credibility. We also tend to avoid makeup especially in the lab or the field. Wearing makeup tends to get you mistaken for a clerical worker.
Several months ago I suspected that fake nails received far more media attention than real ones did, and did not reflect the preferences of real people despite my daughter's protestations that "everybody" wore fake nails. I never seemed to see any on her classmates except for special events such as Prom. So I did a little bit of fieldwork. I went about my business with a little notebook, and my usual errands took me to a mall, various shops and department stores, several drive-through counters, a hospital, and the office where I worked. As I went, I discreetly counted professional or professional-looking manicures that looked as though someone had exchanged money to make them happen. I classified women's manicures as "none", "polish", "fake" as in long and obviously artificial, or "decorative", meaning an elaborate set of nails with multiple colors, jewels, textures, or more than one pattern that is intended to draw attention to the ring finger. It's very possible that I mis-categorized some French manicures as "none", or a few high-quality fakes as "polish". Most polish jobs were probably done Mustachian-style by the owner of the nails.
In my workplace there were no children, so at the other shops, stores, and mall locations I ignored children and adolescents and focused only on adult women.
At my place of work, one female manager and two engineers had nail polish but none had an obviously fake or decorative look. Three secretaries and one of the janitors had decorative fake nails. None of the security guards had polish and neither did any of the student interns.
At the hospital, none of the doctors or nurses had any manicure or polish whatsoever. Counter staff nearly all wore nail polish however I only noticed two with nails that appeared to be fake, and only one of those sets was decorative.
At the drive-through, nearly every female counter worker had a set of elaborate fake decorative nails, generally complete with added jewels and doodads. The second most common way to wear nails was polished. Very few drive-through employees wore bare nails.
At the mall, clerks tended to wear nail polish but not fake nails. Most customers had no nail polish at all. Only about one in ten women who were not obviously employed at the mall wore nail polish or decoration of any sort, and only about half of those (I'd say about five percent) wore decorative nails. Most food service workers who handled food did not wear polish or nail decoration of any kind at work. This could have reflected company policy of some kind.
Overall, I'd say only five to ten percent of the women who can afford it were wearing fake nails. The ones who do, tend to be concentrated either in entertainment-related industries where a high maintenance appearance is considered necessary, or in very low-end service jobs where it's important to hide dirt that may be under the fingernails.