Sex for money is pretty pervasive in society. Before money was invented it was probably sex for fur, or meat, or sex with one person in exchange for not having sex with anyone and everyone. There are a lot of issues - power, personal safety, ethics and morality and I don't really have a one-size-fits-all view about it.
Most women who work as prostitutes are either mothers doing it for their children or are addicted. There are also "career prostitutes" for whom it is a profession and there is hit and run prostitution - people who do it for a short time for a specific financial goal, including students. Women's position in society is not equal with men's and that is reflected in sexual relationships as in everything else.
A lot of prostitution used to involve older men who were widowed or whose wives were off sex (or off their husbands
). There were a lot of regular relationships. Some women look at it as though they are providing a social service for a reasonable fee. It is said that this has changed, with more younger men paying for sex.
I don't count coerced trafficking as prostitution. It is abduction and rape - I would lock the door on the perpetrators and throw away the key.