I do not completely understand your question because you did not fully explain it. Who is going to restrict women from trading? The gambling site or the women's husband or who?
Do not expect any exchange or country to restrict women from trading, that is not possible. The right that you have, women also have the right. Or maybe you are referring to countries that women are restricted from many activities.
The question also goes to men, why would they be losing money instead of taking care of their family. Trading should be done with small amount of money that you can afford to lose, it is not about gender.
All of your points are very valid. Gender should have nothing to do with trading. My issue is with the mindset behind the suggestion, not who would actually put these suggestions into action. It seems especially unfair to put limits on women due to the fact that certain women lose money in trading. That idea feels so old.
All traders, be it men or women lose money in trading when they don’t have the proper knowledge, experience, risk management, or emotional control. Losses are attributed to bad trading strategies and nothing to do with whether you’re a woman or a man. As you said so well, loss should be expected in trading, and so all traders should only trade with the money that they can afford to lose. That is the rule for all traders.
So restricting women would not solve any problem. All what traders need is a good education, you should be disciplined and responsible trading practice for all traders. Not trading on whether or not you are a man or a woman. It is not about restrictions, the focus should be about learning and improving people and not about limiting people based on gender.