I would like to make two other points that I do not believe I saw in this thread.
One is that most previous generations of Jewish women worked very hard, using their hands for housework and things that our generation does not understand. Scrubbing floors has been replaced with sponja or mopping, laundry was a day-long job even with help from a laundry woman, often requiring taking large heavy baskets of clothes to the river or putting large pots on the fire to boil water to clean the clothes in them. None of these activities are very conductive to nail polish staying on the fingers, and if it is chipped and peeling, it is no longer attractive, so why start? Only in the very upper classes who could afford household help and the woman did not engage in these activities would you find women indulging in coloring their nails. This would preclude most Jewish households in previous generations.
Another thing is that nail polish would have to be removed, if I’m not wrong, when removing all chatitzos when going to mikvah. I know that Shopping is not yet a married woman, so this does not concern her, but it is probably one reason why she does not see too many married ladies with nail polish in her community. I do not know if nail polish is considered a chatitzo when washing hands for bread.
What does anybody have to say about ruach ra in the mornings that is supposed to rest on the fingertips (or is it just on the nails)? Just curious about that aspect of it.