Thanks for offering your thoughts. It seems your idea of fairness involves a lot of discrimination.
Suppose Serena William and ‘Martin’ are the same age. They both took up tennis at the same time. They both worked equally hard. And they are both disadvantaged, but in different ways. Whilst Serena is female. Martin is only five feet tall, couldn’t afford tennis lessons and didn’t have a parent who could coach him for free. Martin today is slightly better at tennis than Serena, but whilst Serena gets to make millions and win multiple Grand Slams, Martin doesn’t get to make any money from tennis at all.
That, to me, doesn’t seem fair at all. And it’s an unfairness created by our discriminatory rules.
Life is sometimes unfair. Some people are born stronger or smarter than others. But we don’t have to create additional unfairness by using needlessly discriminatory rules in sport.
Also: you say about girls being able to develop in to “all they could be” — but might it be the case that female tennis players, for example, might actually become better players if they had to compete, on a regular basis, against men? Mixed-sex tennis divisions might easily produce better female tennis players than segregated divisions produce. Would you at least concede that that is entirely possible?