kasha, you have a very simplistic and unhealthy view of the term that a woman is merely a chefetz.
1. a chefetz cannot refuse not to be bought. A woman may choose not to marry at all. Unlike a man, a woman has no chiuv to get married.
2. Were a woman an object to be aquired then she would not be able to refuse a person who wants to aquire her, like a slave could not refuse to who would buy him, or a chefetz demanding who it’s owner should be.
That is regarding whether a woman is an object.
There is a completely different factor of whether women are equal to men. Now of course those who believe that women are mere objects will surely not think that women are equal to men. However since women are NOT objects we can discuss equality. As I have already pointed out on a previous post, women are different but equal to men. How that is carried out in terms of how a husband treats a wife is depended on the makom.
Now halacha doesn’t change, however lets take an example of a slave. You have all the halachas in the Torah regarding a slave. Were a person to own a slave in modern times, even if he acts within the parameters of halacha, he will be considred a cruel person by everyone, including the Rabbis.
Therefore, while halacha doesn’t change minhag hamokom does and it would be cruel to treat a wife as women would be treated in Chazal’s or Rambam’s times.