Why not just ban those who aren't either verifiably male or female from competing?
What's that you say? It's unfair that these people, through a genetic quirk and no fault of their own, can no longer compete in international athletics? Well boo hoo, neither can I, so go get a real job like the rest of us.
There's no need to ban them. Because of what the goals are and how every sport works out, the relevant categories are "female" and "not female". The point of the article is that the sporting bodies need to come up with clear well defined rules that don't leave the athletes sitting there not knowing whether they qualify.
When the point of a contest is to discover the best at some particular skill, fairness is an essential component of the rules.
While individuals may try to subvert the system for their own advancement, the spirit of competition is to win and win fairly. Winning because a challenger gets disqualified for silly reasons is less desirable than winning, as the saying goes, "fair and square."
What's that you say? It's unfair that these people, through a genetic quirk and no fault of their own, can no longer compete in international athletics? Well boo hoo, neither can I, so go get a real job like the rest of us.