Bring back harems where the well off have multiple spouses? I feel like the way inequality is going some places might end up like this or already are. Its usual

Bring back harems where the well off have multiple spouses? I feel like the way inequality is going some places might end up like this or already are. Its usually religion that prevents this. Would sugar babies fall into this category (pay for a relationship and them using that money for school). Maybe a slightly more modern approach would be group relationships, each person specializing in a different life area/role? Anybody watch The Expanse? The problem with such setups is that they are often rife with abuse in some form or another. The person who controls the money controls the group/harem. Isn't this how the world worked before women gained voting rights and ability to work in the labor force. Seems the best way to have an equal partner relationship is to make similar amounts of money with similar amounts of education.