I think you are confusing sports as a social activity and sports as a competitive activity. Take all the money out of sports and let people play however they want is fine. Many people prefer co-ed activities, and the competition can be quite good.

But once you introduce money, even at the collegiate level with scholarships or at the high school level where young people compete for scholarships, and especially at the professional level, where the money can be quite substantial the whole dynamic changes.

There are some mixed gender competitions, that only limit the number of male athletes that can be on the field at one time. Typically, any team that did not field the maximum number of male athletes gets slaughtered.

Women fought hard to have access to sports scholarships and professional sports activities. With nearly half the world comprised of people that are 100% biologically female (regardless of their gender identification), I think we will end up with two sports division.

The "Open" division will allow anyone to compete as long as their bodies are not subject to human performance factors including blood doping and certain steroids.

The X division will be comprised of people, who must meet the same restrictions as the "Open" division with the added requirement, that their bodies have not been influenced by testosterone. This restriction is not new. Fifty years ago, East German women were being "doped" with drugs including testosterone. As a society, independent of the political issues surrounding gender, it would be wrong to allow the use of testosterone by women athletes because of its impact on their bodies long term.

But, if you ban a substance, it should apply to all athletes competing in that forum. The issue has gotten confused by all of the gender debate, the issue is a biochemical one and how to keep sports interesting my keeping them competitive.