If the main issue with showing hair is that it looks beautiful and attractive, why does the obligation to cover hair apply only to married women – unlike other halachos of tznius?
Also, why not object to women wearing jewelry or makeup?
The answer is that the halachos of hair covering are very complex, and most major poskim permit wearing a sheitel, since a big aspect of the halacha is indeed a gezeiras hakosuv – hair attached to a married woman’s head should not be seen.
Differentiating between sheitels that look more realistic versus less realistic is also mistaken. The concern of maris ayin in this context was addressed already long ago, and the poskim who permitted sheitels ruled that maris ayin does not apply here – not because the sheitels of their time were more obviously fake, but because people know that authentic-looking sheitels are commonly worn, so there’s no reason to suspect a married woman of uncovering her hair.
The issue isn’t so much as to avoid things that trigger men, wearing a sheitel shows that a woman is married. I was out with a married woman who was wearing a lace sheitel. A man started up with her. When she told him she was married, he yelled at her for wearing such a sheitel!!.
What’s your source that the reason for sheitel was to publicize that a woman is married, to stop immodest men from flirting (and then he blamed her!!)?