Prohibition creates problems. It doesn't solve them. Prohibiting anyone from using conventional payment infrastructure simply pushes them into the arms of the (sometimes abusive) people who have the resources to work around the system. In this scenario, an individual can't work around the system. The nameless/faceless owners of the large porn groups can.
This situation creates an inherent power imbalance that incentivizes coercion.
In the Snapchat/Onlyfans model, coercion is eliminated by virtue of allowing people to express themselves, when they want and as they want in the privacy of their homes. They are the directors, gaffers, editors etc. and no one else can tell them what they can or can't do.
A decentralized system is better at taking power away from those objectively awful people than any regulation or personal tips or oversight could.
Some of it maybe. But not the toy selling business being discussed.
EDIT: I would like to expand my previous comment though. Whenever prostitution is legalized we see massive improvements in the lives of sex workers. It seems clear to me that further reducing the demonization of sex, sex workers, etc would lead to a better work place in those industries for similar reasons. There may be a baseline of evil, for the reasons you point out. I don't think that should stop us from working to at least reach that baseline, rather than just leaving the people and businesses that inhabit that crucial landscape to rot.
What do we mean by "sexism" here? You don't think it's enough that men would like to have sex with attractive women? Or is that fact itself sexism?
There are dark sides. It is not the friendly industry oft portrayed. It is an industry that thrives on the young and naive. It is regulated because it needs to be. Most common complaint heard by lawyers in the field: "I did the shoot, the movie is on the website, but I haven't been paid." Followed worryingly by: "They said I had to because I had signed a contract."
The advice I give to anyone going to work on their first porn shoot: Bring a friend. Someone older, with a car, who will be on the set with you at all times.